SPECIFICATIONS

EARTHWORKS
Generally

A. The Contractor is to visit the site, inspect and decide for himself the nature of the ground and sub-soil to be excavated. Trial holes and borings may have been carried out on site and in the event that they have, the results will be available for inspection at the Architect’s office. In making this information available, the Employer will not in any way absolve the Contractor from his responsibilities to inspect, nor will it be quarantined that similar conditions apply on other parts of the site.

B. Soft spots in foundation excavation are to be excavated down to firm ground and filled with concrete (1:3:6 - 37.5mm aggregate) under load bearing walls or with broken stone or gravel, well consolidated under non-load bearing walls.

C. The bottom of all excavation is to be thoroughly level, shall be tamped solid and approved by the Architect or Engineer before any concrete is placed thereon.

Where the bottom of excavations deteriorate after approval, due to water or other causes, the Contractor must excavate further to sound undisturbed ground immediately before concrete is placed.

D. Should the Contractor excavate to a greater depth or width than shown on the drawings or instructed by the Architect, he shall, at his own expense, fill in such greater depth or width with concrete (1:3:6 - 36mm aggregate).

E. If the presence of rock can facilitate shallower excavation or reduce the need for foundations as designed on the drawings, the Architect shall be consulted and his permission obtained before any variation from the drawings are undertaken.

F. The existing levels of the site are to be agreed by the Architect and Contractor before excavation is started.

Approval

G. The setting-out shall be approved before work commences and all excavation, filling and hard-core is to be approved before being concreted or covered up.

The Contractor must give reasonable notice to the Architect whenever it is intended to cover up any work and shall, in any default of such notice and if requested by the Architect, uncover (and later backfill) such work at his own expense.

Method of Measurement

H. The excavation has been measured on the assumption that any bulk excavation (e.g. to reduce levels, basements, semi-basements, etc.) will be executed first and the depths stated for all other excavations refer to the depths below the level of such bulk excavation.

I. The volume of excavation, disposal and filling has been measured net as before excavation and disposal or after consolidation of filling, and the Contractor shall make due allowance in his rates for bulking and compaction.
S/1
EARTHWORKS - CONT’D

Disposal of Earth

A. The term “get out” shall mean all work involved in removing excavated material before wheeling or trucking away.

B. Prices for wheeling and depositing or trucking away of surplus earth on or off the site, shall include for any double handling, except that resulting from a written order from the Architect to deposit earth in temporary soil heaps, pending its final removal.

C. Where spoil is removed from site and unless otherwise specified herein, the Contractor shall be responsible for finding a suitable tip and for paying all necessary fees and charges in connection therewith.

Prices of excavation

D. The prices for excavation shall be deemed to include for:-

a) Excavating in whatsoever nature of ground is found to exist *(with the exception of existing brick or concrete foundations or hard rock, which in the opinion of the Architect, require the use of pneumatic drills, wedges and levers, or explosives for removal, in which case an additional item has been measured to cover this extra work)

b) Timbering to, or otherwise upholding the sides of excavations, the extra volume of excavation and backfilling involved, and the cost of reinstatement and/or damage due to the omission or failure of such temporary supporting work.

c) All allowance for increase in bulk and subsequent disturbance during building operations.

d) Well ramming, levelling and preparing surfaces of ground to receive concrete.

e) Removing stones and boulders not exceeding one cubic yard in size, roots up to 150 mm in diameter and any other minor obstructions which may be met with.

Blasting

E. Where excavations are to be carried out by blasting, the written authority of the Architect must be obtained before such operations are begun. The Contractor must inform the Architect of his proposals to safe-guard surrounding property and must take all responsibility for any damage or annoyance caused by reason of blasting.

F. The Contractor must ensure that the charges are not excessive, that charged boreholes are properly protected before being fired, and that all unfired charges are removed from boreholes and that proper precautions are taken for the safety of persons and property.

* Delete in cases where rock has not been measured separately (e.g. when it is known that rock constitutes more than 90% of ground condition.




S/2

Selected Excavated Material

A. All filling must, unless otherwise ordered, be selected dry excavated material arising from the excavations. It shall be free from all roots, vegetable matter, lumber, builder’s debris or rubbish and must be placed, watered and compacted in 9” layers to obtain solid compaction.

Imported fill material

B. Where fill has to be brought to the site, to make up for shortages of surplus excavated material, it must be dry granular material such as dump sand, marl or earth. It must be free from clay, vegetable matter and other deleterious material which could affect the ultimate stability of the compacted filling.

Filling, watering and compaction must be carried out in layers not exceeding 150 mm thick.

Hardcore

C. Hardcore must be hard broken, graded stone, bricks, concrete or other approved inert material. It shall be well rammed and consolidated and where laid to received concrete, must be blinded with hard clean fine material (e.g. sand or crusher dust) free from earth or vegetable matter.

Antiquities

D. Any historical relics, coins or other curiosities, which may be discovered or excavated during the progress of the work, are to remain the property of the Employer and are to be handed over to the Architect.

























S/3
CONCRETING


Generally


A. Rates for concrete floors or slabs are to include for finishing with a tamped finish unless otherwise described.

B. Rates for reinforced concrete are to include for filling into formwork and tamping around reinforcement, both of which have been measured separately, unless otherwise described.

C. Rates for reinforcement are to include for cutting to length, bending as required, hooking at ends and for all tying wire, supports and spacers to provide correct concrete cover.

D. Rates for formwork are to include for any extra work in forming kickers either shown on the drawings or required in construction.

E. Should the Contractor propose using ready-mixed concrete, he must first submit full details of his proposed arrangements to the Architect in writing.

F. In addition to any special provision made thereafter as to sampling and testing of materials by particular methods, sampling of all materials and workmanship proposed to be employed in the execution of the Works shall be submitted to the Architect for his approval. The samples, if and when they are approved, will be kept by the Architect who will rejects all the materials or workmanship not corresponding in quality and character with the approved samples.

Cement

G. The cement shall be from an approved source and shall comply in all respects with J.S. 32:1974. It shall be delivered in the original sealed bags of the manufacturer and be transported and stored in such a manner as to prevent deterioration and/or damage from water. Any cement which arrives on site hot from manufacture, shall not be used until one week has passed.

H. Cement which is more than three months old or in which there are hardened lumps or cakes, shall be rejected.

Fine aggregate

I. The fine aggregate shall consist of well graded coarse pit or river sand free from dust, alkali, organic matter or other deleterious substances.

J. The grains shall all pass through a 5 mm mesh and 90% shall be retained on a No. 100 B.S. sieve. It shall be well graded between these limits and shall be thoroughly washed if requested by the Architect.

K. Under no circumstances will beach or dredged sea sand be allowed in the Works.




S/4
CONCRETING – CONT’D

Coarse Aggregate

A. The coarse aggregate shall consist of natural gravel, crushed gravel or crushed handstone free from shale, dust, silt, alkali loam, organic matter or other deleterious substances 37.5 mm (Nominal) aggregate shall be graded so as to wholly pass through a 37.5 mm gauge mesh and be retained on a 9 mm gauge mesh. 18.75 mm (Nominal) aggregate shall be graded to wholly pass through a 18.75 mm gauge mesh and be retained on a 5 mm gauge mesh.

Samples of Aggregates

B. Samples of each type of aggregate from alternative sources, are to be submitted for testing at least two weeks before it is desired to commence deliveries. The coast of these tests shall be the responsibility of the Contractor.

Cement mortar and grout

C. Cement mortar shall consist of one part by volume of Portland cement and three parts by volume of sand. The constituent materials shall be accurately gauged and mixed in an approved manner. Any mortar which has begun to set or which has been mixed for a period of more than one hour shall be rejected.

D. Cement grout shall consist of Portland cement and water mixed in proportion of one part by volume of cement and one and a half parts of volume of water. The grout shall be used within one hour of mixing.

Water

E. The Contractor shall provide at his own expense, water for all purposes and shall notify the Architect of the proposed source of supply. Only fresh clean drinking water from the public supply shall be used.

Proportions of Concrete

F. The nominal mixes of concrete referred to hereafter, shall have the following quantities of aggregate PER 94 LB. BAG OF ORDINARY PORTLAND CEMENT and the coarse aggregate shall be of the nominal maximum sizes stated. In addition, the minimum works crushing strengths for each mix are listed in the last two columns.

Mix
1
Nominal
Mix
Dry Sand

Coarse
Aggregate
Maximum
Aggregate
7 Days
Strength
28 Days
Strength

A.

B.

C.

D.
1:1 1/2:3

1:2:4

1:3:6

1:4:8
1 1/2

2

3

4
3

4

6

8
18.75 mm

18.75 mm

37.5 mm

37.5 mm
3,000

2,275

1,750

-
3,750

3,000

2,250

-

S/5

CONCRETING – CONT’D

A. Admixtures shall not be used in concrete without the specific approval of the Architect.

Mixing concrete

B. Materials for concrete shall be measured in approved gauge boxes on a boarded platform. The proportions referred to above are for dry aggregate and due allowance shall be made for the moisture content, to the satisfaction shall be made for the moisture content, to the satisfaction of the Architect. The amount of mixing water shall be sufficient to give a good workable mix, but in no case shall the SLUMP (as measured in accordance with standard slump test procedures) exceed 2.5 mm in the case of vibrated reinforced concrete, 75 mm in case of unreinforced concrete. In no case shall the water: cement ratio exceed 0.55. The mixing shall be carried out in approved mechanical batch mixer. Mixing shall continue until there is a uniform distribution of materials and the mass is uniform in colour and consistency. When hand mixing is permitted by the Architect, the materials shall be deposited on clean mixing boards and turned over at least three times and thoroughly mixed in a dry state. Sufficient water shall then be added to bring the mass to a proper consistency, the whole being again turned over at least twice whilst the water is added.

Testing of concrete and materials

C. The Contractor shall be responsible for paying all charges and expenses in connection with testing concrete and materials.

D. In respect of each concrete mix, the Contractor shall make routine tests at frequent intervals using approved apparatus in the presence of the Architect and shall record the results. The tests shall be as follows:-

a) The sampling and testing of aggregates (to comply with B.S. 812)

b) The tests of water control and for workability

c) Tests for compressive strength (to comply with B.S. 1881)

E. The test cubes shall be made in sets of six and shall be stored and tested strictly in accordance with B.S. 1881

F. Six cubes shall be taken for each 100 cubic yards and a minimum of six cubes shall be taken for each day’s pour, and for each change in cement content, aggregate or consistency during a day’s pour.

G. Cubes shall be cast in steel moulds, 160 mm x 150 mm x 150 mm and shall remain in the moulds for 3 days.

H. The cubes shall be made from concrete drawn from newly laid concrete or concrete about to be placed in position and cast in the presence of the Architect. Cubes shall be marked with a reference number for identification to define the mixing plant, the class of mix, the location in the structure of the concrete from which the sample was taken and the date cast.

S/6
CONCRETING – CONT’D

A. The cubes shall be sent by the Contractor to an independent testing laboratory approved by the Architect. Three cubes of each set shall be tested at seven days and the remaining three cubes retained and tested at twenty eight days.

B. Copies of the results of all tests shall be sent by the testing house direct to the Architect within 24 hours of the test.

C. In all cases where the concrete tests fail to meet the required strength, the Architect shall order, at the Contractor’s expenses, the taking of cores for check strength tests, and/or replacement, or strengthening, of those portions of the structure where concrete is found to be less than the designed strength.

Handling and placing concrete

D. No concrete shall be deposited until the formwork or formation has been approved by the Architect. As soon as possible after mixing and before the initial set has taken place, the concrete shall be deposited directly on to a water tight platform or into a water tight receptacle ready to be deposited immediately into position.

E. The concrete may be distributed in barrows, skips, chutes, or by any other approved method.

F. The concrete shall be worked up against the formwork with a long trowel, very great importance is attached to the depositing and thorough ramming of the concrete, to ensure that it is homogeneous and free from interstices.

G. The use of mechanical vibrators to ensure maximum compaction is essential. They shall be of an approved design and capable of vibrating at 5,000 oscillations per minute. Care shall be taken to see that no vibration is transmitted to any concrete which has taken its initial set.

H. All surfaces of concrete work which have set, shall be thoroughly cleaned and wire brushed and shall be ‘roughed up’ before any fresh concrete is deposited against them; when the surfaces have been properly prepared, they shall be brushed with a neat cement and water grout.

I. In hot weather, as soon as the concrete has commenced to set, its surface shall be covered with tarpaulins or hessian cloth, which shall be kept continuously wet for a period of seven full days following the date on which the concrete was laid.

J. The use of propriety curing membranes will be permitted if approved by the Architect.

Formwork

Formwork is measured to actual surface in contact with the concrete and prices are to include for all splayed edges, notchings; allowance for laps and passings at angles; battens, struts, bolts, nails, wedges; treating with mould oil; striking, easing and removal. The number of times the formwork may be reused shall be taken into account in pricing.

K. The formwork must maintain the concrete in its correct position during placing, compaction, setting and hardening without loss of any material, and provide against its own deformation under load.
S/7
CONCRETING – CONT’D

A. For all insitu work, the Contractor may use either timber or steel shuttering. Other materials may be used for formwork providing requirements of strength, etc. Are met and they are to the satisfaction of the Architect. All shuttering shall be in every respect adapted to the structure and to the specific surface finish to the concrete.

B. The formwork shall be constructed so that side shutters to concrete can be removed without disturbing soffit shutters.

C. Immediately before concreting, the forms shall be thoroughly cleaned out, temporary openings being provided for this purpose if necessary.

D. Concrete shall not be placed until forms have been inspected and approved by the Architect.

E. The inside surfaces shall then be coated with mould oil or an approved material to prevent adhesion of the concrete. This material must not come into contact with the reinforcement and shall be such as will not cause any stain or disfiguration of the concrete.

F. Formwork shall not be removed until the concrete has matured sufficiently to permit the formwork to be removed without causing damage to the member. Subject to other requirements of this specification, the following table may be taken as a guide for the removal of the formwork.


MEMBER OR LOCATION
ORDINARY
PORTLAND
CEMENT CONCRETE



Beam & lintel sides, walls and columns
DAYS

3

Soffits of slabs (props left under)

7

Soffits of beams & lintels (props left under)

7

Removal of props to slabs

10

Removal of props to beams and lintels

18

G. At the Architect’s discretion honeycombed areas and voids in remaining exposed concrete shall be chipped out square with the existing surface, the surface roughened and wetted, and carefully patched with mortar to match adjacent concrete, the face of the patch being finished flush.

H. Side shutters shall be eased and then removed as early as possible to permit inspection and efficient curing of the concrete surface.

I. Unless the structure is fully propped, it may not be subjected to any loading beyond its dead load until at least 28 days after casting when ordinary Portland cement has been used.

S/8

CONCRETING – CONT’D

A. When it is proposed to prop from or otherwise load any part of the structure during the course of the work, the Contractor must first obtain agreement of the Architect to the proposed arrangement of props and loading.

‘Fair face’ Formwork

B. Where formwork is described to give ‘a fair smooth surface’ the concrete shall be brought to a fair and even surface in casings, by working the concrete against the casing during pouring. Immediately after removal of the casing, the concrete surfaces shall be trowelled over to remove any irregularities, air holes, etc. And shall be stopped with cement mortar (1:3) to the requirement of the Architect. The face of the concrete shall be rubbed down with carborundum stone, dipped in cement grout to a perfectly true, smooth and even surface, free from all board and joint marks, honeycombing, pitting, etc. Such work shall be commenced within one hour of removing the shutter and actively and rapidly performed until completed, the object being to complete the finish as soon as possible after the removal of the suttering. The Contractor may also provide a smooth lining which will achieve the required finish without rubbing down. All rubbed work shall be lightly washed with plain cold water on the completion of the Contract and not before, at least four weeks after pouring.

Construction joints

C. Construction joints shall be formed at right angles to the axis of the member. Vertical joints shall be formed by the insertion of rigid stopping off forms. The position of any construction joints not shown on the drawings shall be subject to the approval of the Architect. The upper surface of lifts of concrete columns shall be horizontal and the shuttering shall not extend above the joint on the exposed face.

D. All construction joints shall be formed with keyed bulkheads. Reinforcement shall continue through the joint, and additional reinforcement shall be provided, as called for on the Drawings.

E. Joints shall be located at the centre of the span, as shown on the Drawings and shall be so spaced that the placing of concrete shall be continuous between joints.

F. Where expansion and contraction joints occur within a structural member, the joints shall be of uniform width and continuous throughout the whole of the section of the member, to the external finish.

G. The expansion joints shall be filled with an approved filler to within 1/2” of the finished face and then pointed with an approved sealing compound to finish just proud of the finished surface.

Removal of formwork

H. The following clauses apply especially to reinforced concrete and are supplementary to those preceding, which shall be read in conjunction with them so far as they are applicable.

I. The Contractor shall be responsible for any injury to the concrete work and for any damage caused by or arising from the removal and striking of formwork and supports or the moving, hoisting and transport of precast or other work.

S/9
CONCRETING – CONT’D

A. On the written instructions of the Architect, the Contractor shall remove and reconstruct, at his own cost, any portions of the work which in the opinion of the Architect give evidence before or after the removal of the formwork that the concrete at the time of depositing was of inferior quality, or that any bars of the reinforcement have been omitted or displaced, or which shows evidence of any faults, defects or injury from any cause whatsoever which in the opinion of the Architect, may prejudicially affect the strength or durability of the construction.

Holes in concrete members

B. No holes or other cavities shall be cut in any concrete work unless approved. The Contractor shall ascertain from the drawings from sub-contractors or from elsewhere, particulars of all bolts or other fixings, and of all openings, holes, pockets, chases, recesses and other cavities, so that before placing the concrete, all bolts and fixings shall be in position, and any other inserts necessary for forming holes and other cavities shall be fixed to the shuttering.

Steel reinforcement

C. The steel rod reinforcement shall comply with J.S. 33:1974. Steel fabric reinforcement shall comply with B.S. 1221 Part A. All reinforcement shall be free from pitting, loose rust, mill scale, paint, oil, grease, adhering earth or any other matter which in the opinion of the Architect may impair the bond between the concrete and the reinforcement or which causes corrosion of the reinforcement or disintegration of the concrete..

D. The size and position of the reinforcement shall be strictly in accordance with the drawings, and the reinforcement shall be fixed in position, inspected and approved by the Architect before any concrete is placed. Suitable precautions shall be taken to prevent displacement of the reinforcement during concreting, during which a steel fixer shall be available.


E. All reinforcing rods shall be bent to shape on the site of the works or other place approved by the Architect. Bends and turns in rods up to 25 mm in diameter shall be made cold. Rods exceeding this diameter shall be heated to a dull red heat but not cooled by quenching. Bending shall be done with an evenly applied force, without jerk, in a bending machine or approved pattern. Any rod which shows signs of cracking at a bend shall be rejected.

F. Where rods cross, or come into contact, they shall be wired together with No. 16 iron binding wire with three turns before twisting and ends cut off 1” from twist with cutting pliers. Rods connected longitudinally shall overlap not less than shown in Clause 310 of B.S. C.P. 114 and shall be securely wired. Ends of plain rods in tension shall be bent over to a radius of four diameters or as otherwise shown or specified.

G. Reinforcement shall be properly braced, supported by the spacers, chairs, etc. Or mortar pads if directed by the Architect and held firmly in position so that the placing and ramming of the concrete will cause no distortion or displacement of the reinforcement. Any temporary supports shall be removed during concreting.

H. The stirrups, links or hoops connecting the rods, shall be taut so that the rods are properly braced. The inside of their curved parts shall be in actual contact with the rods around which they are intended to fit.

S/10


CONCRETING – CONT’D

A. The effective cover to reinforcement shall be in accordance with Clause 307 of B.S. C.O. 114 unless otherwise specifically noted on the Drawings.

B. The weights of reinforcement are computed from the sizes and net lengths of the rods shown on the drawings. The actual weights used for each diameter bar, are as follows:-

Diameter of
bar

Weight in kg.
Per m.
Diameter
of bar
Weight in kg.
Per m.

1”

2.670

12 mm

0.888

7/8”

2.044

10 mm

0.616


3/4”

1.502



5/8”

1.043

6 mm

0.222

The prices of all reinforcement shall include for all cutting to lengths and waste, straightening, bending including in special radii, hooked ends, cranking, space bars, cover blocks, tying with and including binding wore and for all other matters necessary for the supply, preparation and fixing of the reinforcement.

C. The cement and fine aggregates are to be as specified under Concreting:























S/11
WALLING AND MASONRY

Concrete Blocks

A. All hollow concrete blocks shall be two hole blocks of approved manufacture to comply with J.S. 35:1975 with a minimum crushing strength in accordance with Table 4 of the Standard and samples shall be submitted to the Architect before commencement of the Works.

B. Hollow concrete blocks described as in ‘load bearing walling’ shall be Clause A blocks and shall be tested as set out below. The test results shall be submitted in duplicate to the Architect and his approval obtained before any blocks in consignment are used.

a) 10 Blocks out of each 10,000 shall be tested for crushing strength.

b) 10 Blocks out of each 10,000 shall be tested for absorption.

Mortar

C. The mortar used for block laying shall be composed of one part cement to four parts of sand.

D. All mortar shall be properly mixed upon a clean platform and shall be used as mixed and no mortar which has been allowed to set prior to use shall be used in the work.

E. Mortar in load bearing walling shall have a minimum compressive strength of 1,600 lbs. Per square inch at 28 days. Tests shall be carried out on 50 mm cubes and three cubes shall be tested for every 250 square yards of walling laid. Test results shall be submitted in duplicate to the Architect for approval.

Laying

F. All blockwork shall be laid in stretcher bond, properly bedded, jointed, flushed up in mortar and carried up regularly around the building. All blocks shall be thoroughly watered before laying.

G. Reinforced cavities above ground level and every cavity below ground level shall be filled in solid with concrete (1:3:6) placed and consolidated in sections not exceeding 1200 mm in height.

H. Concrete block units shall be wet immediately before being laid and the effective shells and webs shall rest and align one over the other.

I. All joints in the wall must be flushed solid as each course of block is laid.

J. Work is to be frequently checked with levelling instruments and all angles, reveals, etc. are to be strictly ture, square and plumb.

Reinforcement

K. Reinforcing steel shall be placed as shown on the drawings. Minimum overlap of all reinforcing bars shall be 48 diameters. In calculating the weights of reinforcement to hollow concrete blocks, bars have been measured in one length from base to top. Allowance has been made only for laps with starter bars at foundations and for tying into reinforcement of concrete beams, slabs and the like at the top and elsewhere. Unit rates shall allow for any other labours and laps required.
S/12
Rates to include

A. The rates for concrete block walling shall include for plumbing and bonding at all angles and intersections, cutting at jambs and sills and otherwise cutting and fitting up to concrete soffits, forming reveals and returns.

Fair faced block walling

B. Fair faced block walls shall be built from selected blocks of matching colour and texture. Each course shall be laid perfectly level with joints of equal thickness and all adjacent exposed faces laid flush with each other. Properly calibrated coursing rods or templates shall be set up at the ends of every panel of walling to facilitate correct alignment of the block courses. Pointing shall be carried out as the work proceeds and unless otherwise described in the Bills of Quantities. All horizontal and vertical joints shall be slightly recessed and have a half-round concave profile. Excess mortar must be cleaned off before it hardens.

C. All external corners, jambs and reveals must be built perfectly square and vertical, and, whenever possible, fair ended blocks shall be used in these locations. When special fair end blocks are not available, all exposed recessed block ends must be filled up with cement mortar and finished off smooth and flush with adjacent blocks.
Lintels

D. In the absence of any other details, all normal builder’s lintels shall be the same thickness as the wall and not less than 200 mm deep with not less than 200 mm bearing at each end and shall be reinforced with steel bars hooked at each end and placed 1” above their soffits as follows:-

100 mm wide and under, 1 No. 12 mm diameter bar for clear spans up to 1200 mm with 6 mm stirrups at 150 mm centres.

For lintels over 100 mm wide and up to 200 mm wide, 2 No. 12 mm diameter bars for clear spans up to 1200 mm, 2 No. 16 mm diameter bars or 3 No. 12 mm diameter bars for clear spans up to 2100 mm with 6 mm stirrups at 150 mm centres.

E. The Contractor shall refer to the drawings for reinforcement details of all other lintels.
Ends

F. All free vertical ends of walls such s window and door jambs or jambs to opening shall be reinforced with 10 mm diameter bar not more than 100 mm from the edge.

Stone Walling

G. The stone walling shall consist of selected river or limestone finished to the thickness as shown on the drawings and where specified shall be hammer dressed. Stones may be random size and shape but are to be carefully selected so as to ensure that stones of varying sizes shall be roughly cut to the complimentary sizes of this neighbour so as to avoid mortar joints thicker than 25 mm.

H. The stones shall be dressed and roughly cut on the site and shall be further cut as may be necessary when laying.

I. All stones shall be thoroughly wetted just prior to laying. Stones shall be bedded in cement mortar composed of one part of cement to three parts of sand.

S/13
ROOFING


General

A. The Main Contractor shall supply and install all nailing blocks, curbs, cant strips, and blocking and shall do all carpentry work related to roof framing.

B. Head flashings at plumbing vent stacks through the roof shall be supplied and installed by the roofing contractor.

C. Rainwater outlets through the roof shall be supplied and installed by the Main Contractor. Dressing to outlets shall be part of this Division.

Base

D. All boarded or screeded bases shall be swept off and cleaned before water-proofing work commences. Any projecting nails or lumps or mortar shall be removed.

E. Commencement of work implies acceptance of base and any work condemned afterwards by the Architect, shall be rectified at the Roofing Sub-Contractor’s expense.

Protection

F. Provide protection against falling roofer’s materials and against possible damage through execution of the Contract.

Cleaning

G. Thoroughly overhaul the roofs and leave sound and watertight upon completion.

Asphalt Roofing

H. The asphalt roofing shall be mastic asphalt manufactured in accordance with B.S. 988 and laid in accordance with the relevant Standard Code of Practice.

I. The asphalt roofing shall be laid in the number of coats and to a minimum thickness as described in the Bills of Quantities, and shall be laid on and including an isolating membrane of black sheathing felt.

J. The asphalt roofing shall, unless otherwise described, be finished with white limestone chips which pass 10 mm mesh or an approved light reflective paint as described.

K. The whole of the asphalt work shall be carried out by an approved firm of asphalt roofing specialists. The whole of the asphalt work shall be covered by a written guarantee against all defects in materials and workmanship for the period stated in the Bills of Quantities.






S/14
ROOFING – CONT’D

Built-up felt roofing

A. The roof finish, where specified, is to be of two or three layer built-up bituminous felt as described in the Bills of Quantities, laid on prepared surfacing, and to bear a 5 year guarantee given by the Contractor to the Building owner before completion of this Contract.

B. The materials are to be as follows:-

Bitumen - an approved brand of coal tar pitch

Felt - waterproof, acid proof and alkali proof tarred wood to comply with British Standard 747.

C. All materials must be best quality obtainable.

D. The first layer of felt shall be in 900 mm wide weighing 4.8 kg. Per 12 metre length, to be laid in the direction of the fall and nailed to the sarking with broad head felt nails spaced 250 mm apart along the sides and centre of each roll and at all ends and laps, or stuck to the concrete slab with hot bituminous compound. Side and end laps shall be a minimum of 50 mm and properly sealed.

E. The second layer of felt shall be in rolls 900 mm wide weighing 7.4 kg. per yard length, to be laid in hot bituminous compound at the rate of 15 kg per 10m2. Rolls are to be laid in the direction of the fall but joints staffered with those below.

F. The top layer of felt shall be standard grey or mineralised finish in rolls 900 mm wide weighing 14.4 kg per 12 metre length. To be laid in hot bituminous compound at the rate of 15 kg per 10 m2. Rolls are to be laid in direction of the fall but joints staffered with those below.

G. Where the top layer of felt is standard grey finish, a top dressing of white limestone chips which pass 10 mm mesh, shall be rolled into a coat of bituminous compound to a thickness of 12 mm.

H. All layers are to be properly dressed at junctions with vertical surfaces and around ventilating pipes etc., passing through the roof as shown on the drawings and in an approved manner.

Shingle roofing

I. Materials are to be as follows:-

Shingles - Canadian red cedar No. 1 perfections, or the best quality locally available end grain sawn and cut from the block at right angles to annular rings with a nominal length of 400 mm and random widths.

Nails - Copper or galvanised mild steel wire nails to B.S. 1202

Flashings Aluminum or galvanised steel not less than 26 gauge.



S/15
Shingle roofing - cont’d

A. Shingles shall be laid to the gauge specified with 37.5 mm medium side lap, each shingle twice nailed to battens or sarking. Eaves and verges shall be formed with a double course breaking joint. Valleys shall be open cut and flashed with sheet metal. Where roofing area meet at hips and edges, the shingles shall be accurately cut and mitred and capped with shingles lapped alternately, unless otherwise shown on the drawings. Sheet metal under and over-flashings shall be provided at abutments.

Aluminium sheeting

B. Aluminium sheeting shall be obtained from a manufacturer approved by the Architect and shall conform to B.S. 3428. Unless otherwise noted, sheeting shall have a stucco finish and natural colour.

C. Sheets shall be fixed through the ridges or corrugations with long stainless steel screws having neoprene washers bonded to the underside of heads. Wood fillets shall be provided under the corrugations at all fixing positions. Unless otherwise shown on the drawings or noted in the Bills of Quantities screw fixing positions shall not be further apart than alternate corrugations across the sheeting and 900 mm down the length. The maximum horizontal spacing at eaves shall be halved.

D. Preformed ridge cappings, verge and abutment flashings of the same material and colour as the main roofing, shall be provided. Cappings and flashings shall be secured with stainless steel self-tapping seam screws into ridges of corrugations in the roof sheeting. Fixing shall be spaced not more than 450 mm apart and at laps and intersections. Laps in ridge cappings shall be caulked with a non-hardening caulking compound or “Tremco” tape placed between the over-lapping sections.

E. At the top edge of sheets covered by a ridge capping, the ends of all valley corrugations shall be neatly turned up to prevent the ingress of blowing rain and vermin.

Galvanised steel sheeting

F. The corrugated galvanised steel roof sheeting shall be “Galvon” or other approved manufacture, having a minimum zinc coating of 2.14 kg/m2. Only best quality sheets shall be used.

G. The method of laying and fixing shall generally be similar to that specified for aluminium sheeting, except that twisted galvanised dome headed nails shall be used for securing the sheets and flashings.

Gutters and Down Pipes

H. Metal gutters and down pipes shall be compatible with the roof sheeting they are draining and shall be of the sizes and shapes shown on the drawings. Laps shall be caulked with an approved waterproofing material and securely fastened together. Appropriate supporting hangers or brackets shall be provide at close enough centres to prevent sagging or bending in the particular member.



S/16PAVING


Materials generally

A. The cement, sand and water shall be as specified in ‘Concreting.”

Cement Paving

B. Cement paving shall be composed of cement and sand (1:3) laid to the thickness required to achieve the levels shown on the Drawings.

Concrete floors and Walls

C. Where concrete floors and walls are specified, the surfaces of the slab, while still green, shall be sprinkled with dry cement and worked with a steel trowel or wood float to an even and regular finish and to the falls as noted on the drawings. The construction the slab, if necessary for the future protection of the paving, shall wherever possible be delayed until such time as the heavy trades have moved from the area being paved.

Beds and screeds

D. Cement screeds shall be composed of cement/sand (1:3) laid to the thickness required to achieve the falls shown on the drawings. They shall in no case be less than 20 mm thick.

E. Before laying screeds, the concrete surfaces shall be chipped if necessary to form a key and then thoroughly cleaned and wetted with water. A coat of cement slurry shall be applied to the surface of the slab as the work proceeds and the screed shall be laid before the slurry sets. The screed shall be kept wet for at least seven days after laying.

F. Steel or wood float finishes to floor screeds or concrete slabs shall be perfectly smooth and true and shall be free from all trowel marks or other defects and imperfections.

Cement and Terrazzo floor tiling

G. Floor tiles shall be pressure made and locally manufactured and shall be of approved colour and pattern. All tiles shall be fully cured and undamaged. Any tiles warped, chipped, grazed or damaged in any way will be rejected. Three representative samples of all types of tile proposed for use shall be deposited with the Architect, and when accepted, those incorporated in the works shall not deviate there from. Floor tiles shall be soaked in clean water immediately before laying and bedded wet in cement mortar (1:3). They shall be set out in both directions from the centre lines of the area being paved and bedded to the levels shown, and to falls and currents where so indicated.

H. Floor tiles shall not be disturbed for twenty four hours (24) after bedding and grouted with an approved tinted grout. The tiles shall be protected against all damage, staining and wear until finally cleaned off and polished immediately before the works are handed over.

I. Unless otherwise noted, terrazzo tiling shall, after laying and grouting, be honed, neutralised and sealed.


S/17
Vinyl Floor Tiling

A. Vinyl floor tiles shall be of the size and thickness stated in the Bills of Quantities and of a colour to be selected by the Architect. They shall be laid in approved adhesive by a Firm approved by the manufacturers and in accordance with their instructions. Setting out shall be as for terrazzo tiling and they shall be protected and finally polished before handover. Rates for vinyl floor tiling are to include for any necessary latex levelling screed where tiling is laid direct on concrete floor slabs, and for laying alternate colours in a checkerboard pattern.












































S/18
CARPENTRY, JOINERY AND HARDWARE

Timber generally

A. Softwood unless otherwise stated shall be pressure treated pitch pine to the approval of the Architect, suitable for the purpose for which it is intended and at least 85% heartwood and is to be well seasoned and sawn square all round, free from excess of wane or discoloured sapwood, injurious open shakes, large, loose or dead knots, all signs of rot termites, worms and beetles and other defects.

B. All hardwoods shall be 100% heartwood.

C. All doors and other joinery items shall be stored under protective cover away from damp surface or locations.

Description of pitch pine

D. Where described as ‘pitch pine’ it shall mean sawn or dressed as the Contractor chooses.

E. Where described as ‘dressed pitch pine’ it shall mean all additional planning, glass papering and scraping to a finished surface to receive decorations or other finish treatments.

Sizes

F. All rough timbers, and dressed timbers, where finished sizes are given, shall be of the full dimensions shown. Where nominal sizes are shown the finished sizes may be up to 3 mm less for each surface planned.

G. All sizes of dressed timbers in these Bills of Quantities are nominal sizes unless otherwise stated and the Contractor should allow in his prices accordingly.

Preparation

H. All screw and bolt heads or nuts are to be countersunk and exposed nail heads are to be driven in below the surface of the timber and filled for finishing.

I. All woodwork is to be delivered on the site and approved by the Architect before it is primed. The bottom and top edges of all doors and surfaces of all frames and other dressed timber to be built into masonry or concrete openings shall be primed one coat before fixing in position.

J. The word ‘framed’ is to be understood as including all the best known method of joining timber by mortice and tenon, splice and dowell or otherwise.

Keep Clean

K. All dressed surfaces shall have a glass papered or scraped finish for decorations as required.

Timber described hereafter as ‘selected’ shall be selected and kept clean for polishing, varnishing, staining or oiling and prices shall include for matching adjacent pieces of timber to the same colour, to this end, staining of timber will not be permitted.

S/19CARPENTRY, JOINERY AND HARDWARE – CONT’D
Defective work

A. Any joinery that splits, shrinks or warps from want of seasoning and unsoundness or bad workmanship shall be removed and replaced without charge.

Fixing

B. Where softwood or hardwood is described as planted on, nails shall be punched and the holes stopped.

C. Where hardwood is described as fixed to bearers or screwed on, it shall be secretly fixed with screws or countersunk screwed and pellated.

D. All screws used for fixing softwood or hardwood are to be obtained from an approved source.

E. All work described as plugged is to be fixed with hardwood plugs well rammed into holes drilled with a rotary drill.

F. Unless otherwise described, plugging for fixing timbers shall be at such intervals as will provide adequate fixing to the approval of the Architect.

G. Door frames shall be fixed to jambs with steel lag screws located 225 mm from head and foot and at 900 mm maximum centres between. Heads of frames exceeding 900 mm wide shall be screw fixed to adjacent soffits at 900 mm maximum centres.

Prices to include

Prices for Carpenters work and timber framing, skirtings, architraves, stops, bearers, frames and fillets, etc. Shall include for all short lengths, mitres and ends, housing, notchings, halvings and other sundry labours of a like nature

Prices for all joinery work shall include for slightly rounding all exposed arrises

Flush Doors

H. Flush doors shall be obtained from an approved manufacturer to comply with B.S. 459, faced both sides with plywood panels with hardwood lippings as required. External quality plywood shall be used in external doors.

Plywood

I. All plywood shall be of waterproof quality.

Hardware

J. All hardware is to be as specified and samples shall be submitted to and approved by the Architect before ordering. The prices for hardware shall include for all temporary screws required, for preliminary fixing, for temporarily removing to allow painter to complete his work, oiling all working parts and re-fixing with screws provided by manufacturer. All furniture shall be fixed with screws of the same metal and finish, as the fittings.

S/20



CARPENTRY, JOINERY AND HARDWARE – CONT’D

A. Keys shall be stamped with their corresponding lock numbers by the factory or supplier and shall be tagged for location immediately checked with operation and handed over to the Employer.

Kitchen Fittings

B. Joinery fittings are to be manufactured and installed by a manufacturer or Sub-Contractor approved by the Architect. The Contractor should note that the drawings indicate the general arrangement of the kitchen cupboard units, but the detailed layout will be left to the particular manufacturer selected, and shop drawings together with samples of laminate and hardware, must be provided for the Architect’s approval before any work is ordered or executed. The Contractor must indicate the Sub-Contractor selected and any change of Sub-Contractor must be notified to the Architect for his approval.





























S/21






GENERAL METALWORK


Fabricated steelwork

A. All steel and ironwork shall have rust and scale removed by scraping or wire brushing immediately before painting and all shop-prefabricated work is to be primed with one coat approved rust inhibiting primer before delivery to site or fixing.

B. The Contractor shall supply shop drawings of all specifically fabricated items for the approval of the Architect. Welds shall neatly filed down smooth and units shall be pre-fabricated in the shop wherever possible. Only the minimum site welding shall be employed. All screwed work shall have full internal and external threads and all holes shall have burrs cleaned off. Counter-sinkings where required, must be concentric.

Metal windows and jalousies

C. The Contractor shall be responsible for the prompt ordering of metal windows and other factory made articles, and shall satisfy himself that they arrive on site in perfect condition and shall arrange for their storage and safety until such time as they are installed and the building handed over.

B. The Contractor shall be responsible for the metal windows and jalousies being set straight, plumb and level and for their satisfactory operation, including any gearing after fixing is complete. The windows shall be fixed at head, jambs and sill and care shall be taken to ensure that they are not distorted when tightening up fixing screws.

D. The windows shall be fixed into prepared openings and shall not be forced into openings which are out of square or too small. The openings shall allow at least 3 mm tolerance all round.

E. After fixing, the windows must be sealed all round with caulking compound. The caulking compound shall be non-hardening, non-staining, shall not sag or run and shall receive paint without bleeding. It shall be applied with a propriety caulking gun.



















S/22
PLASTERING AND WALL TILING

Cement

A. Cement shall be as described in ‘Concreting’

Sand

B. Sand shall be hard, clean, sharp, naturally occurring pit or river sand or crushed stone or gravel, free from all vegetable, clay or animal impurities, and well stored to prevent contamination from sand impurities.

C. Sand for backing coat shall pass a 16 gauge sieve.

D. Sand for finishing coats shall pass a 24 gauge sieve.

Rendering

E. Rendering for internal and external use and to receive tiling shall consist of one part Portland cement to four parts sand (1:4), and is to be applied in two coats to a total minimum thickness of 16 mm, unless otherwise described. Smooth rendering shall be finished with a wood float to a fine granite finish.

F. The surfaces to be rendered shall be well wetted before the finishing coat shall be thrown on from the trowel, levelled with a straight edge and brought to a smooth finish as described.

G. The whole of the finished surfaces of the rendering shall be flat and finished to a fine, smooth finish; where the rendering has been damaged by rough usage, the rendered face shall be re-executed.

H. All making good or patching shall be cut out to a rectangular shape with undercut edges so as to form a dove-tailed key, and finished flush with the surrounding surface.

Tyrolean rendering

I. Tyrolean rendering shall consist of a backing coat of cement and sand (1:4) of a thickness as specified followed by a tyrolean finishing coat of an approved shade, produced by a suitable mix of crusher dust and white cement applied with a cement spraying machine and built up to a total thickness of 6 mm, all to the approval of the Architect.

Rough stucco rendering

J. Rough stucco rendering shall consist of a backing coat of cement and sand (1:4) as specified followed by a finishing coat of cement and sand (1:4) worked to give rough adobe type finish to the approval of the Architect.

Pebble dash finish

Pebble dash shall be applied to external walls in two coats. Pebbles shall range in size from 6 mm - 12 mm and shall be thrown on dry to a 12 mm thick cement and sand (1:3) backing coat at the rate of 0.10 tons per square yard. Pebbles shall be free from clay, vegetable or other deleterious matter and be obtained from a source approved by the Architect.
S/23

PLASTERING AND WALL TILING – CONT’D

Screeds

A. Screeds shall be composed of cement and sand (1:3) and be properly laid to rules set to the required levels, falls and currents and floated to a surface suitable to receive the finishing described or to the finished surface required.

Making Good

B. Protect plastering, screeding and tiling and make good damage during progress and on completion of other trades, including hacking off and replacing all hollow or loose areas, and leave all perfect and to the satisfaction of the Architect.

C. Co-operate with other trades in incorporating accessories and framing for openings and do all cutting and patching as reasonably required.

Wall tiling

D. The wall tiles shall be standard quality white to B.S. 1281, true to shape, free from all blemishes and from a manufacturer approved by the Architect. All external angles shall be rounded and shall bond with the tiling on each side. Tiles shall be fixed to walls with ‘saxit’ or other approved tile adhesive, cleaned off and grouted and painted in white cement.

General

E. The prices for plastering and tiling shall include all necessary dubbing out to obtain a true plane, extra labour working behind and around pipes and brackets, etc. Forming neat angles and supplying, fixing and clearing away all temporary rules and battens required, working plaster to frames and other surfaces.

F. The prices for forming fair edges and arrises shall include working the plaster to adjacent surfaces such as fairfaced concrete, metal, etc.

G. Unless otherwise described, insitu finishings are applied to concrete or concrete block surfaces, the keying of which has been measured separately where necessary.















S/24
PLUMBING

By-Laws

A. The whole of the plumbing work shall be executed in accordance with the Bye-Laws of the Public Health Authority and/or other competent authority.

Galvanised Tubing

B. The service and waste pipes are to be galvanised mild steel to B.S. 1387/57 ‘heavy’ gauge with screwed joints made with strands of fine hemp and an approved propriety jointing compound or alternatively with plastic jointing tape.

C. The fittings are to be galvanised malleable iron to B.S. 1740.

D. Where pipes are surface fixed they shall be secured at regular intervals with galvanised metal holderbats plugged and screwed to walls or soffits.

U.P.V.C.

E. U.P.V.C. pipes shall conform to J.S. 39:1975 and pipes and fittings are to be manufactured by Thermo Plastics (Jamaica) Ltd.

F. Waste and ventilating pipes are to be P.V.C. SDR 32.5 and 64 pipes with matching fittings.

G. Cold water service pipes are to be PVC Schedule 40 pipes with matching fittings unless otherwise specified.

H. Pipes shall be cleaned and jointed with solvent cement in accordance with the manufacturer’s printed instructions.

I. All surface fixed pipes shall be held in position with holder bat type brackets spaced in strict accordance with the pipe manufacturer’s instructions, plugged and screwed to walls and soffits.

Prices for Pipes

The pipes have been measured net length as fixed and the Contractor shall allow for all cutting and waste, holder bats to walls, floors, ceiling and making good all trades after

The prices for all pipes are to include for all short lengths, sockets, unions, connectors and back nuts

Workmanship

J. The work shall be executed by fully qualified tradesmen in accordance with the drawings and authorised modifications thereto, to the satisfaction of and as directed by the Architect.

K. Ventilation pipes shall terminate not less than 450 mm above roof level and finish with a stout wire balloon well secured.All junctions for waste services shall be made with swept fittings and every waste branch shall have adequate means of rodding.

S/25

PLUMBING – CONT’D

A. All waste fittings are to be properly trapped with 37.5 mm seal traps of suitable types.

B. All taps and valves shall be dismantled and greased before fixing.

C. The full bore of the pipework shall be maintained throughout and all internal burrs shall be reamed out.

D. Vertical pipework shall be installed perpendicularly.

E. All pipes are measured nett as fixed, measured over all bends, tees, etc. and rates shall include for all short running lengths, sockets, running joints and connectors, backnuts, all cutting and waste and making good around pipe supports. Elbows, tees and other such fittings are measured separately and rates shall include for extra joints, cutting and waste.

Sanitary fittings

F. All sanitary fittings, fixtures, stop valves, etc. are to be carefully installed strictly in accordance with the manufacturer’s printed instructions. Fittings and fixtures are to be installed with the proper tools and to be left in perfect working order and free from all tool marks or other damage. The Contractor will be responsible for obtaining accurate roughing-in and setting out dimensions for the various fixtures and for locating supply and waster pipes accordingly,

Water Supply

G. The supply pipes are to be set out to provide for the isolation of fittings and for emptying down the system.

H. Services shall be installed to ensure positive automatic clearance of air.

Chasing

I. Where pipes are to run in walls, floors, etc. prices of these pipes are to include cutting horizontal or vertical chases in hollow concrete block walling, concrete walls, floors or ceilings large enough to accommodate the full diameter of the pipe and socket and making good with cement mortar (1:3) flush with adjacent surfaces. Pipework to be fixed in chases, shall be installed before the final rendering coat is applied.

J. All pipes, whether soil, waste, ventilation or service, are to be concealed in pipe ducts or in wall chases or ceilings or under floors unless otherwise particularly noted on the Drawings.

K. Access panels shall be formed wherever necessary to give access to cleaning and stopcocks.

Testing

L. Water services shall be tested under main pressure.

M. All waste, vent and soil pipes shall be tested by means of air or hydraulic pressure to 3 lbs. per square inch, the gauge to remain steady for 5 minutes.

S/26
PLUMBING – CON’D

A. Access plugs, caps and doors shall be removed, greased, refitted and made sound prior to the final testing.

B. If inspection or test shows defects, such defective work or material shall be replaced and inspection and test repeated. Repairs to pipes, etc., shall be made with new material.

General

C. The whole of the work, materials and fittings shall be adequately protected against damage and deterioration, any such damage or deterioration shall be made good and the work handed over at completion in a sound and clean condition and in perfect working order.






































S/27

ELECTRICAL INSTALLATION

General

A. The Electrical Contractor shall arrange for all labour and the supply and installation of everything necessary in the Electrical System.

Licence

B. The Electrician shall possess a Government Electrician’s Licence and shall be subject to the approval of the Architect.

C. The work includes the complete electrical installation and supply of fittings up to and including the supply and fixing of potheads and accessories required for main supply.

D. The Electrical Contractor shall supply and subsequently remove any fittings and fixtures required at fixture outlets to allow inspection by G.E.I.

E. Prices are to include for the installation of all lighting fixtures and other equipment supplied by the Owner, provided these are furnished to the Electrical Contractor by the Client not later than one month after date of practical completion.

Materials

F. All switches, plugs, sockets, cables, fuses and other materials shall conform to the current British Standard Specification where such exists, unless otherwise specified.

Wiring Diagram

G. The Contractor shall supply complete electrical circuit wiring diagrams of the scheme in accordance with the requirements prior to commencement of the work and an ‘as built’ drawing at the completion of the work.

G.E.I.

H. The whole installation shall be carried out as indicated on the Drawings and in all respects, in accordance with the requirements of the Government Electrical Inspector and the local Electrical Supply Authority.

Conduit

I. P.V.C. Conduit of adequate size but not less than 3/4” shall be used throughout and shall be laid to drain off condensed moisture.

J. Conduit boxes for termination at lighting prints and for general use throughout the installation, shall be circular B.B.S.A. Spout Boxes 2” fixing centres.

K. All conduits shall be concealed by building in during the progress of the Works and the Main Contractor shall be responsible for ensuring that conduit is located in good time so as not to delay his own building programme.

S/28
ELECTRICAL INSTALLATION – CONT’D

Locations

A. The locations of all lighting points, switches and convenience outlets shown on the Drawings, are approximate and are to be set out on site for the Architect’s approval. Any points laid out without the Architect’s approval, shall be relocated if required by the Architect at the expense of the Contractor.

B. Generally, wall switches are to be mounted 1.35m above finished floor level and at a distance of 150 mm from edges of door frames and convenience outlets are to be mounted 450 mm above finished floor level.

C. Switches and convenience outlet plates are to be ‘MK Plate Switches’ square or equal and approved pattern ivory colour, reference 38/31 and to be fixed with matching rustless screws.

Circuit Labels

D. All circuit breaker panels boards shall be provided with labels indicating the circuits controlled by each particular breaker and in general the rooms or fixtures contained in these circuits.

Cooker Panel

E. Cooker panel to be MK reference 5282 metal clad indicating switched outlet with lamp, but with ivory plate Reference 5223 in lieu of aluminium.

Convenience outlets

F. Not more than four (4) convenience outlets re to be wired per circuit.

Switchgear

G. Provide main switchgear and power and lighting breaker panel in steel cabinet. Panel to include four (4) spare circuits to be fully recessed into wall and complete with door.

H. All exterior light points, switches and junction boxes shall be weather proof type approved by the Architect.
Meter

I. Meter shall be 220 volt 3-phase 4 wire whole current socket type meter up to a maximum rating of 100 Amps. The Contractor shall provide, install and connect the socket suitable for use with outdoor meter. The socket should be installed on an exterior wall at a point nearest to the available incoming supply and should be mounted not less than 1500 mm and not more than 2100 mm above ground. The socket should be surface mounted or recessed in the wall with at least 12 mm projecting from the wall surface. The cases where customer-owned service lines with one or more poles are erected on private property the meter socket should be located on the first pole on private property nearest to the Company’s lines from which the supply is to be taken. The first private pole should not be more than 30 m from the Company’s take-off pole.

For 3-phase meters for voltages other than 220 and for all 3-phase installations requiring currents in excess of 100 Amps, A-Base metres with instrument transformers, as necessary, will be used as hitherto.
S/29

ELECTRICAL INSTALLATION – CONT’D

Testing

A. During progress and after completion, the Works shall be tested for electrical continuity, insulation, conductivity and polarity in accordance with Section 5 of the I.E.E. Regulations, 13th Edition.

B. Allow for testing the whole of the Electrical and Telephone Installation and certifying that the whole of the installation comply with the requirements of the Government Electrical Inspector.









































S/30

GLAZING

Glass and Glazing

A. The whole of the glass shall be the best of its respective kind, free from all specks, waves, bubbles, scratches and other defects, and shall be of the respective weights and types indicated in the Glass Distribution Schedule below and on the Drawings.

B. All broken or cracked panes shall be replaced at completion of the Works and the whole of the glazing left clean and perfect. Provide all necessary washleather or velvet glazing strips.

C. The putty for use in glazing to woodwork, shall be composed of best linseed oil and whiting.

D. Glass jalousie blades shall have both exposed edges properly ground to eliminate all corners and projections.

E. All glass (unless fixed with beads or with washleather strips) shall be back puttied, sprigged and pegged with copper pegs, puttied, cleaned off and neatly finished.

F. In cutting glass, proper allowances shall be made for expansion. Each pane of glazing shall be in one whole sheet.

Glass Distribution Schedule

G. All exterior and interior panes, except as specifically noted otherwise on the Drawings, shall have maximum allowable size per pane as follows:-

1 kg Clear sheet - 2.95 metres

2 kg Clear sheet - 5.87 metres

5 mm Float glass - 3.3 metres

5.5 mm Float glass - 4.2 square metres

















S/31

PAINTING

Materials

A. All painting materials and colours shall be approved by the Architect and shall be equal to the best quality products of Berger Paints Ja. Ltd., West Indies Paints Ltd., Brandram Henderson (W.I.) Ltd or Sherwin Williams Co. (W.I.) Ltd. All paints and painting materials are to be strictly in accordance with the latest standard manufacturer’s specifications.

Sample boards

B. The rates for painting shall include for the provision of 600 mm x 600 mm sample boards showing the colours and tints of the various paints to be used for the approval of the Architect prior to painting.

Preparation

C. All surfaces are to be prepared with the correct primers, sealers and stopping as required by the manufacturer’s instructions for each type of paint and surface and shall be applied accordingly.

D. All paints shall be thoroughly mixed or stirred before use. They shall be so stored and sealed to minimise exposure to drying and extremes of temperature.

E. All defective rendering shall be cut out and made good in approved fashion before painting. Slight cracks shall be made good with hard stopping.

F. All removable metal fittings are to be taken off before the preparatory processes are commenced and are to be re-fixed on completion of the final costs.

G. All steel and ironwork before painting is to be scraped and cleaned with wire brushes until all grease, scale, rust and loose substances are removed. Each coat is to be carefully and evenly applied. No coat is to be applied until the previous coat is hard, dry and free from moisture.

H. All paint on woodwork shall be rubbed down with fine glass paper between each coat. Each coat shall be hard, dry and free from moisture or condensation before the next coat is applied. The final gloss coat shall not be thinned with turpentine or other thinning agent.

I. All woodwork specified as painted is to be primed before being fixed in position.

J. All knots are to receive two coats of knotting applied thinly and well brushed in. Loose knots shall be removed and the holes plugged with sound wood. Large knots shall be cut back and made good with hard stopping.

K. In no case shall any paint or distemper be applied to concrete or rendered surfaces until such surfaces are completely dried out and clear of efflorescent tendencies.

L. The final coat of painting shall be applied after all dirty trades have been completed. The protection of the finished work and touching up, shall be the Contractor’s responsibility.


S/32PAINTING – CONT’D

Workmen

A. Only skilled workmen are to be employed. A properly qualified painting foreman is to be constantly on job while the work is in progress.

Parti-colours

B. The Contractor is to allow in his rates for executing the whole of the fore-going work in parti-colours as may be directed by the Architect. The prices for painting in narrow widths shall include for cutting to line on all edges as required.

Covering Power

C. If any of the painted or decorated surfaces are deficient in covering power or show excessive brush or roller marks further coats must be added at the Contractor’s own expense to the entire satisfaction of the Architect.

Back Priming

D. All exterior trim shall be back-primed before installation with approved exterior base coat and all interior trim with approved enamel undercoat. Tops and bottom edges of doors shall be treated with one coat of primer before being fixed in position.

Rates for painting blockwalls and concrete

E. The Contractor shall allow in his rates for painting fair-faced blockwalls or board-formed concrete surfaces with a sealer coats as necessary prior to application of emulsion or oil paint.

Sta-Dri

F. Where ‘Stay-dri’ paint is specified on concrete or block surfaces, it shall be obtained from Facey Commodity Hardware Ltd., and applied in two coats strictly in accordance with the Manufacturer’s instructions.

Completion

G. Allow for thorough cleaning of all floors, fittings, etc., cleaning all glass both sides, touching up paint work where necessary, clearing away debris and rubbish and handing over the building in a satisfactory condition to the approval of the Architect.










S/33
DRAINAGE

Regulations

A. The Contractor shall conform with the regulations and bye-laws of the Public Health Authority and/or other competent authority.

General

B. Materials and workmanship shall be of the best quality and executed in accordance with the Specification and Drawings as supplied by the Architect and to his approval and satisfaction.

Materials

C. The sand, aggregate, cement and steel shall be as specified under ‘Concreting’.

D. Hollow concrete blocks shall be as specified under ‘Walling’.

E. Cement mortar shall be as specified under ‘Walling’ for hollow concrete block walling.

F. P.V.C. Pipes and fittings shall be as manufactured by Thermo Plastics (Jamaica) Ltd., laid and jointed in accordance with the Manufacturer’s printed instructions.

G. Glazed earthenware pipes and fittings shall be locally manufactured and of the best quality available.

H. Asbestos cement pipes and fittings shall be as manufactured by Caribbean Asbestos Products Ltd.

I. Cast iron pipes shall be in accordance with B.S. 437 and fittings to B.S. 1130

J. Concrete pipes and fittings shall be obtained from an approved manufacturer and shall be in accordance with B.S. 556.

K. Prices for fittings on all types of drain pipes shall include for extra joints, cutting, waste.

Workmanship

L. The drains shall be laid to suit the general progress of the building work and at such time in such manner as to be adequately protected against damage and deterioration. The whole of the work shall be handed over in a sound and clean condition on completion of the Contract.

Excavation

M. The excavations for drains shall be made to true and even falls and the bottom shall be trimmed to the correct level and well rammed.

N. Suitable handholes shall be provided at all joints to allow access for jointing. These holes shall be carefully filled in after jointing. The widths of trenches at the bottom shall allow for not less than 150 mm clearance between the outside of the pipe and the face of trench or timbering the same.


S/34
DRAINAGE – CONT’D

A. Wherever soft places in excavated surfaces are encountered, the Contractor shall excavate the soil to a hard foundation and fill up with concrete or other suitable approved material before any drains are laid.

B. Any trenches excavated in error to a greater depth than is required, shall be filled up to the required level with concrete (1:3:6) at the Contractor’s expense. Trenches shall be left open until all drains, manholes, etc. have been tested and approved.

C. The whole of the back-filling to asbestos cement or cast iron drain pipes, shall be properly consolidated and shall be executed in 225 mm layers, each layer being separately consolidated. No mechanical rammers shall be used until at least 600 mm of consolidated material has been returned over the pipes.

D. Only approved material shall be used for backfilling.

E. Where extra over drain excavation for excavating in rock has been measured, that Contractor is to understand that the following trench widths have been allowed and that similar widths will be used when measuring variations in drainage work. Under no circumstances will the Contractor be entitled to an extra on account of trench widths being greater than those set out below:-

Size of Average width
Drain Pipe Depth of Trench allowed

100 mm Not exceeding 900 mm 550 mm
100 mm 925 mm to 1500 mm 650 mm
100 mm 1525 mm to 2250 mm 800 mm
150 mm Not exceeding 900 mm 600 mm
150 mm 925 mm to 150 mm 675 mm
150 mm 1525 mm to 2250 mm 800 mm

Jointing

F. Joints on cast iron and spun iron pipes and fittings shall be made with best quality tarred spun yarn, caulked in and finished off to not more than one third of the depth of the socket. The remaining space shall be filled with molten lead well caulked. All pipes and fittings shall be securely held in position while joints are being made.

G. Joints on asbestos cement pipes shall be made with a coupling consisting of an asbestos cement sleeve and two rubber rings. Coupling shall be assembled in a workmanlike manner using coupling pullers and in accordance with the manufacturer’s instructions. After assembling the coupling, the positions of the rubber rings shall be checked with a suitable gauge. Both rings for the full circumference of the pipes, shall be located at even distance from the coupling ends. Care must be taken while jointing to prevent dirt entering the joint chase.

All stoneware pipes shall be laid dry, true to line with spigots set square in the sockets and closely butted and shall be jointed with one ring of tarred yarn, well caulked and with cement and sand (1:2) packed into the socket and finished off with a bold collar on the outside, trowelled smooth and wiped clean of all surplus material on the inside as the work proceeds. All concrete pipes shall be laid true to line and jointed in cement mortar (1:2) and finished off as described for stoneware pipes.
S/35
DRAINAGE – CONT’D

Concrete encasures

A. The pipe drains shall be laid to line and grade in the position shown on the Drawings. Pipes passing beneath the buildings or under roads with less than 120 mm cover, or elsewhere with less than 750 mm or more than 4.2 m cover shall be totally surrounded with not less than 150 mm of concrete (1:3:6). In any other condition, stoneware pipes shall be haunched and properly supported by bedding material specified.

B. With regard to the types of bedding which may be specified, the following conditions shall be observed:-

1) Where concrete bedding is specified, a bed of concrete (1:3:6) shall be laid under the pipe. The width of the bed shall be 300 mm plus the nominal diameter of the pipe for pipes less than 9” diameter and for pipes 9” diameter and over the width of bed, shall be 375 mm plus the nominal diameter. Pipes shall be supported on the barrels and not on the sockets during laying.

2) Where haunching of pipes is specified, this shall consist of:-

Concrete bed as in (1) above.

The full width of the bed carried up to the level of the horizontal diameter of the pipe in concrete (1:3:6).

Splay in concrete (1:3:6) from this level carried up both sides of the pie from the full width of the bed, to meet the pipe barrel tangentially.

Haunching shall be carried out only after testing the drains.

3) Where surround to pipes is specified, a bed shall be laid as in (1) above, except that in all cases, the thickness shall be 150 mm and after testing the pipes, shall be completely surrounded with concrete (1:3:6) to give a minimum thickness of 150 mm over the barrel, the finished concrete being approximately square in section.

Where the diameter of a drain is increased in size, the soffits shall be maintained level and the drop in invert shall be made by using a suitable taper pipe.

Manholes, septic tanks, etc.

C. Unless otherwise described, rates for manholes, septic tanks, etc. are to include for the following:-

1) Excavate to the sizes and depths required, and form manholes where shown on the Drawings, return, fill in and well ram in 250 mm layers around walls and foundations and wheel surplus excavated material and spread and level over site where directed.

2) Provide all necessary planking and strutting.

3) Trim, level and well ram bottom of excavation to receive concrete.
S/36
DRAINAGE – CONT’D

4) Provide and lay bed of concrete (1:3:6) 150mm thick for manholes up to 1800 mm deep and 250 mm thick for manholes over 1800 mm deep as foundations.

5) Build the walls to the heights and sizes shown on the Drawings in hollow concrete blocks in cement mortar, with all cavities in blocks filled with concrete (1:3:6 with 12 mm nominal single size aggregate).

6) Provide concrete (1:3:6) filling to bottom and form benching with vertical face rising from channel edges to height of main drain crown and form upward slope therefrom, at a gradient of 1:6 to meet manhole wall and finish with a cement and sand (1:3) trowelled smooth.

7) Form half round main channels and branches in benching to falls as required.

8) Provide concrete (1:2:4) cover slabs 150 mm thick as directed with openings for covers and frames. Reinforce with 12 mm diameter mild steel rods as required.

9) Render manholes internally with cement and sand (1:3) 12 mm thick in two coats on concrete block sides and trowel with a steel float finish.

10) Manhole step irons of galvanised malleable cast iron conforming to B.S. 1247 or equivalent J.S. shall be built into walls at 500 mm staffered intervals vertically and 250 mm centres horizontally to all manholes exceeding 1050 mm deep.

Gully Basins

A. Unless otherwise described, trapped gully basins shall be of glazed earthenware “p” or “S” gully trap with galvanised grating, encased 6” all round with concrete (1:3:6). The concrete basin (1:3:6) shall have 100 mm walls all round carried 75 mm above finished pavings or grade 100 mm base dished to outlet, all rendered with (1:3) cement and fine sand to steel float finish with all edges chamfered. The top of the basin shall be rebated for the type of cover and frame required.

Testing

B. The General Contractor shall provide all appliances and necessary assistance for testing.

C. All drains shall be hydraulically tested to a 1500 mm head and no drains shall be covered in nor further proceeded with until such test has been made and repeated as necessary until passed by the Architect.









S/37EXTERNAL WORKS

Generally

A. All work in this Bill is to be executed in accordance with the description of workmanship and materials given at the beginning of each of the foregoing respective trades.

Formation Level

B. Formation level shall be the surface level of the ground obtained after completion of the earthworks; that is the underside of the sub-base or where no base is specified, the underside of the base. Any material unnecessarily excavated below formation level shall be backfilled with material acceptable for construction and compacted as directed by the Engineer and no payment shall be made for the excess excavation or for backfilling and compacting.

Excavation and filling

C. The Contractor shall carry out such scarifying, excavating or filling as may be necessary to form the new sub-grade in accordance with the drawings and shall adhere to slopes, levels, depths and heights shown thereon. Unless otherwise directed or permitted by the Engineer, all suitable excavated materials shall be used where filling material is required.

Preparation of Sub-Grade

D. All filling material used in earthworks shall be compacted, to these Specifications, by plant approved by the Engineer for that purpose. Unless otherwise approved, the filling material shall be compacted at its natural moisture content by 6 passes of the heavy (minimum 8 ton) smooth-wheeled roller. The surface of the formation shall be finished smooth and even and shall not vary more than 12 mm in 3 m in profile and coos-section, and shall have a tolerance of 12 mm and -25 mm compared to levels shown on the drawings.

Marl

E. Marl shall consist of a natural mixture of limestone rock fragments and binder free from soft particles and clay. The material shall pass an ASTM 75 mm sieve, be uniformly graded and shall not have more than 15 percent by weight passing an ASTM No. 2000 sieve.

F. The marl shall have the following gradation:-

U.S. Sieve Percentage by Weight
Size Passing

75 mm 100
50 mm 90 - 100
25 mm 65 - 90
10 mm 40 - 65
No. 4 30 - 55
No. 10 20 - 45
No. 40 10 - 30
No. 200 5 – 15


S/38
EXTERNAL WORKS - CONT’D

A. The fraction of the marl material passing the No. 40 sieve shall have a plasticity index not greater than 6 and a liquid limit not exceeding 28.

Sub-Base

B. The sub-base shall consist of marl. The sub-base shall be evenly spread on the formation without segregation to size and to such loose depth that compacted layers will have a maximum of 150 mm thickness; and compacted by 8 passes of the heavy (minimum 8 ton) smooth-wheeled roller or by other means approved by the Engineer.

C. The sub-base shall be compacted to a dry density of not less than 95% of the maximum density at optimum moisture content by modified AASHO tests.

Marl Road Base

D. The prepared foundation for the base shall be shaped carefully to the required cross-section and compacted thoroughly. All drains, watermains, cable ducts or other special formation work shall be completed before any base materials is placed.

E. The base of approved marl shall be spread uniformly upon the prepared formation in layers not exceeding 150 mm in depth after final completion.

F. The dry density after compaction shall not be less than 95 percent of the dry density for that marl when tested in accordance with AASHO T - 180 Method D, except that the sample being tested shall contain particles of all sizes passing the 37.5 mm sieve instead of passing the 20 mm sieve. A fresh sample shall be taken for each determination of moisture content density relationship.

G. Any portion of the road which is not accessible to the roller, or other compacting units, shall be thoroughly compacted with hand tampers or with approved mechanical vibrators.

Asphaltic Concrete Road Surfacing

H. When the base course has been laid and consolidated it shall be swept clean and uniformly sprayed with M.C.1 cut back bitumen at the rate of (0.25 gallons per square yard). This prime coat shall be kept clean and free from traffic until it is hard. It shall be kept free from traffic except for vehicles loading the paving spreader.

I. The bituminous concrete surfacing shall be of a minimum thickness as specified and generally in accordance with B.S.S. 594, Asphaltic Institute U.S.A. mix Type 4 (b) or other approved standard specification to the Architect’s approval.

J. The material shall be mixed in a hot mix plant and laid and spread by a mechanical spreader and rolled with an 8 - 12 ton roller.

K. The finished surface shall be to the levels shown on the Drawings with tolerance of 6 mm on a 3.60 m straight edge placed in any position and direction on the surface.

L. The Contractor shall make good at his own expense any work which in the opinion of the Architect is not in accordance with this specification, whether caused by bad workmanship or defective materials supplied by the Contractor or any materials made defective by his operations.
S/39
EXTERNAL WORKS – CONT’D

Asphalt surface dressing

A. Asphalt surface dressing shall consist of a prime coat and two sealing coats as described herein.

B. Asphaltic materials shall conform to B.S. 3690 or equivalent J.S.

C. Aggregates shall conform to B.S. 63, single sized roadstone and chippings or equivalent J.S. Aggregates shall consist of clean, hard, dry, tough, sound, crushed stone or crushed gravel of uniform quality, free from dust, clay, dirt and other deleterious matter.

D. The priming coat material shall be a cutback bitumen MC 1 at (the rate of 0.25 gallons per square yard.)

E. The sealing coat material shall be a cutback bitumen MC 1 a (the rate of 0.22 gallons per square yard).

F. The base course should be well consolidated and swept clean and sprayed with priming coat.

G. The first sealing coat shall be covered with 20 mm nominal size chippings at a rate of 90 square yards to one cubic yard or aggregate, and the second sealing coat covered with 10 mm nominal size chippings at a rate of (100 square yards to one cubic yard of aggregate.)

Precast concrete kerbs

H. Precast concrete kerbs shall be battered on half of one face and are to be bedded in cement and sand (1:3) on a concrete base (minimum 75 mm thick), 300 mm wider than the thickness of the kerb. The verge side of the kerb is to be filled with concrete up to half the height of the kerb.

I. Joints between kerb shall be flush pointed.

J. Kerbs shall be cast with concrete (1:2:4) 20 mm aggregate and finished with a smooth fair face finish free from honey combs etc. Each length of kerb is to be reinforced with a minimum of 2 No. 10 mm mild steel rods with 6 mm links at 300 mm centres.







S/40