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Date Posted: 14:15:48 10/17/06 Tue
Author: 何焯華條賓周+歡迎炸佢: jameslam@hkpro.com.hk
Subject: 淨屌何焯華條仆街呢+歡迎炸佢: nancychow@hkpro.com.hk
In reply to: 何焯華條賓周+歡迎炸佢: jameslam@hkpro.com.hk 's message, "淨屌何焯華條仆街呢+歡迎炸佢: nancychow@hkpro.com.hk" on 14:22:02 10/14/06 Sat

SECTION 8.0 DRAINAGE

8.1 Repair/Replacement of External Wall Drainage Systems

Epoxy Coated Cast Iron or UPVC pipes and fixings

a) Take down, clear away and replace all defective external drain pipes complete with all fittings and brackets. Submit shop drawings to the Surveyor for approval prior to installation.

b) The size of the new pipes should not be less than the existing pipe. The Contractor shall fully check on site before tender return.

c) Fix and supply new Epoxy Coated Cast Iron pipe or UPVC pipe complete with all fixings and, including brackets as indicated on drawings. (The Contractor shall fully check on site and follow the existing routing of the pipeworks in his replacement works)

d) Cut or burn out existing joint, clean socket and spigot ends and remake joint

e) Cut into and remove short length of pipes or branch pipes in position and provide and joint in new simple junction complete with loose collar if required. The depth to be hack off surrounding the existing branch pipe shall not more than 25mm from the external wall Surface or where the collar is found inside the wall. New branch pipe will be inserted to the collar inside the external wall. And then the wall surface shall be made good afterwards.

f) Where pipe pass through external wall, the Contractor shall ensure water tight that the hole should be grouted with waterproofed cement sand mortar, pointed the hole surround with approved mastic sealant after making good the finishes.

8.2 Soil & Waste Disposal Systems

a) Soil and waste System shall be carried out according to the combined soil and waste system (one pipe system). All piping materials shall be UPVC and Epoxy Coated Cast Iron should be to match with existing unless otherwise specified.

b) All UPVC pipes and fittings shall be in accordance to B.S. 4514 or Aust. Standard 1415 or approved equal to relevant British Standard.

c) Epoxy Coated Cast Iron pipes shall comply with BS EN877 and jointed in
accordance with the manufacturer's recommendations.

8.3Rain Water System

a Rain water from all roofs shall be collected by rain water outlets and discharged to the rain water dawn pipe.

b. The defective rain water dawn pipe shall be taken down and replaced with new UPVC or Epoxy Coated Cast Iron pipe.

c. In general, rain water drainage system shall be by gravity.

8.4Unplasticized PVC Soil. Waste, Rainwater & Ventilating Pipes


a) Rigid Unplasticized PVC pipes and fittings far Soil, waste, rainwater, and ventilating pipes shall be in accordance with B.S.4514 or Aust. Standard 1415 o approved equal to relevant British Standard, and of the following minimum wall thickness:

Nominal Minimum Wall Thickness
Dia.of Pipe(mm) Pipe(mm) Fittings(mm)
80 3.20 3.43
100 3.20 3.43
150 3.20 3.68

b) Unplasticized PVC pipes and fittings to be jointed by “ Solvent Welding"
method with socket in accordance with the manfacturer’s instruction.

c) Seal ring joint is to be installed between fixed paints which are more than 900mm apart. Far long straight pipe run, seal ring expansion joint is to be Installed at every 3,000mm interval.

8.5Drainage Pipe Fittings

a) On all systems, long radius bends and pitcher tees are to be used wherever possible.

b) Reduction in bore of pipe to be made where necessary level invert reduction should be provided.


c) Access must be provided at the base of all stacks, apposite joints, an bends and elsewhere where required and in such a position that they can be conveniently inspected and cleaned at all times.

d) Cleaning eyes and across covers are to be fitted with grease felt washers and brass or stainless steel bolts. Cleaning eyes and access covers below horizontal pipe are not acceptable.

e) Unplasticised P.V.C. fittings are to be supplied by the pipework manufacturer
and are to be the same standard and quality as the pipework.

f) The Contractor has to submit shop drawing for approval before placing order
for special local cast fittings.

8.6Installation of Pipe Work

a) Pipework shall be carefully arranged ω a neat and workmanlike appearance in true alignment with a minimum number of crossovers.

b) Disconnecting flanged or screwed unions shall be provided at valves and fittings and at suitable locations for cleaning and removal of piping.

c) All pipework shall be free from burrs, rust and scale and shall be thoroughly cleaned before erection. Open ends during the progress of work shall be blanked-off with purpose-made metal or plastic caps and the use of wooden plugs is forbidden. Should any stoppage in the flow occur after the various systems have been put into operation, owing to non- compliance with this requirement, the Contractor shall rectify the fault at his own expense.

d) Pipes are to be installed with correct falls for venting and draining and attention must be paid to neatness of installation. Groups of pipes to be accurately spaced and valves, joints, etc. symmetrically arranged. Where two or more pipes are visible and change direction together, bends shall be struck from a Common radius point. Adequate clearances to be maintained in all cases to allow for the application of the insulation and finishing.

e) All pipework likely to be in direct Contact with concrete shall be coated with a bitumen compound and wrapped in polythene before being concealed.

f) Vertical stacks must be positioned as hard against to wall, columns and fins as possible.

g) P.V.C. pipes to Epoxy Coated Cast Iron sockets should be connected with stainless steel coupling in accordance with the manufacturer's recommendations.

h) Epoxy Coated Cast Iron pipes should be connected by coupling joints, which are to be made in stainless steel (Grade 316) or an approved jointing compound o similar.

i) P.V.C. pipes to cast iron sockets or bossed connections are to be screwed
joints or caulked cement and yarn or approved jointing compound.

i) Valves etc. should be installed in such a manner that future maintenance of
glands etc. is made as easy as possible. All hand wheels must also be accessible.

j) Connections to soil stacks are to be made below the lowest branch serving the floor and the upper end is to join the vent stack not less than 700mm above floor level.


8.7Pipe Supports

Nominal bore Epoxy Coated Cast Iron Pipe UPVC Pipe
Pipe diameter(mm) Intervals (m) Intervals (m)
Vertical Horizontal Vertical Horizontal
15 1.8 1.2 1.5 1.0
20 2.1 1.5 1.5 1.0
25 2.1 1.8 1.8 1.2
32 2.4 1.8 1.8 1.2
40 2.7 2.1 2.1 1.5
50 3.4 2.7 2.1 1.5
65 3.6 3.4 2.4 1.8
80 3.6 3.4 2.4 1.8
100 4.0 3.6 2.4 1.8
150 4.6 3.6 2.4 1.8
200 4.9 3.6 - -
225 4.9 3.6 - -
250 4.9 3.6 - -
300 4.9 3.6 - -
Notes: Not less than 2 supports must be used on all pipes having length less than the minimum intervals indicated.

a) All pipe work, fitting and the like shall be sufficient by supported and bracketed. All pipe work shall be supported at intervals not greater than the above tables for straight runs. Additional individual supports shall be provided at bends, and other heavy fittings to the satisfaction of the Project Manager.

b) Stainless steel (grade 316) pipe-brackets with plastic coated pipe ring shall be used for all external wall pipe services at podium level 2, while hot-dipped galvanized steel pipe-brackets shall be used for internal pipe services. All fixing screws for G.I. pipe supports shall be chromium plated and
stainless steel screws for stainless steel supports. Sample shall be submitted to Project Manager's prior approval.

c) All pipe supports are to be of such design and type as to allow for the removal
of any pipe section without the necessity of disconnecting other adjacent pipes.

d) Where pipe rings are used they are to be split pattern with top and bottom bolts.
For horizontal pipe the rings shall be held by stainless steel rod screwed to
pipe ring boss and in all cases where rocking movement of the pipe ring is
expected spherical seating washers shall be provided to all adjusting nuts.

e) The Contractor shall be responsible for the building in of all supports and
when tendering shall allow for using approved bolt fixing for concrete and
cutting away and building in of brackets in brick work. The Contractor is to
particularly note that it may not be possible to fix and bolt fixings directly
above the pipes to the supported in such event cantilever brackets shall be used
where required.

f) All existing pipes shall be replaced with pipe dimensions as indicated on
drawings. In the case of the pipe diameter specified is less than the existing
system, the Contractor shall notify the Project Manager and seek clarification.

g) All pipes, that locate far away from the wall, column, beam or fin etc. and
cannot firmly supported by pipe brackets, shall be supported with an
alternative method proposed by the Contractor. Otherwise, the support may be
hot dip galvanized steel angle frame that to be supply, design and fixed by the
Contractor.

8.8 Pipe Anchors
a) All pipes shall be anchored as required to control the movement of pipes due
to thermal changes. General anchors are also to be fitted at the lower ends of
vertical pipes.

b) The anchors shall securely hold the pipe in a rigid position to resist the
tempted movement due to expansion and the weight of the pipe and contents.

c) All anchors bolt for external pipework shall be stainless steel.

8.9Pipe Guides

a) Pipe guides, are for use in long lengths of pipe and tube and are to be fitted on each side of every joint to keep and to direct the movement of expansion and contraction from anchor points in true alignment in lateral direction towards the bellows or other flexible inserts shall take the form of enclosing hoops of mild steel flat to B.S. 3974: Part I, generally 40mm x 20mm in section. Such shall be secured to roller brackets and other fixing by means of bracket attachments. Metal guides for UPVC pipes shall be lined internally with UPVC material slightly oversized to allow axial movement of the pipe.

b) Generally, guides shall be fixed at points between the anchors and expansion joints to ensure that the thrust is linear to the axis of the pipe.

8.10Pipe Sleeves

a) Where pipes pass through walls, floors, ceiling, etc. the Contractor shall supply and fix pipe sleeves. Sleeves for PVC, ductile iron, cast iron and galvanized steel pipes shall be black steel. All sleeves are fitted through floors, they shall extend to at least 6mm clear of finished floor.

b) Sleeve shall not be used as pipe support.

c) Sleeves shall be of slightly oversized to allow free movement of pipes.

d) Where vertical pipe ducts pass through floors, the fire barrier shall be maintained with a concrete floor provided by the Contractor.

e) The gap between pipe and the sleeve is to be packed with fibre-glass blanket material. However, for pipes/sleeves through fire barriers, the gaps must be firmly sealed with soft packings (with fire certificate provided) having a period of fire resistance equal to the fire barriers. The ends of sleeves are to be caulked with non-hardening mastic to architect's approval.

f) Concrete curbs shall be constructed at the surrounding of G.I. pipe sleeve passing through floor slab.

g) Details of pipes through walls and floors to be approved by the Fire Services
Department and the Surveyor before installation.

8.11Pipe Movement and Expansion Joint

a) Wherever possible, advantage shall be taken of changes in direction of pipes to take up expansion and contraction due to temperature changes of the pipe contents.

b) Expansion coupling with neoprene seal ring at one end to be used on uP.V.C. piping.

c) On uP.V.C. Vertical/Horizontal drainage mains, axial expansion coupling, as recommended by UP.V.C. pipe/fitting manufacturer, to be supplied and installed as shown on Drawings, of slip type with neoprene seal ring between the two coupling members. Class and standard of expansion joint should be the same as those for pipes specified.

d) All supports for UPVC pipes outside building shall be plastic coated steel soft felt strips are to be provided between the plastic and the clip.

e) All pipe supports to be of such design and type to allow for the removal of any
pipe section without the necessity of disconnecting other adjacent pipes.

f) All fixing screws shall be stainless steel (grade 316).

g) The Contractor shall be responsible for the building in all of all supports etc. and
should allow for using Philips Redhead bolt fixing' for concrete and cutting away and building in of brackets in brickwork etc. The Contractor is also particularly note that it may not be possible to fix the bolts directly above the pipes to be supported and cantilever angles are to be used where required.

8.12Removal of Fixing Bolts, Ties for Temporary Works and Old Steel Pipe Brackets for Old Pipes

a) It is important that fixing bolts and ties for temporary works and steel pipe bracket for old pipes are properly removed from the building upon completion of works. They have to be trimmed off to a depth sufficient (25mm min.) to avoid corrosion and consequential problems to the finishes. Where holes are formed in external walls for bolts ties and steel pipe bracket, these holes should be properly grouted to the satisfaction of the Surveyor with cement mortar to an approved mix prior to applying the surface finishes.

b) At the commencement of the Works, the Contractor shall include in their proposals for the temporary works, the method of fixing and removal of such bolts, ties and steel pipe brackets as may be required and: such should be submitted and approved by the Surveyor.

SECTION 9.0 CONDITION SURVEY OF TILED/RENDERED AREA

9.1 Scone of Works

The scope of work under this section may include condition survey to the building. The contractor shall be notified by the Project Manager on the commencement of survey from time to time, depending on findings and actual condition of building during the contract period. The contractor shall commence the survey within 2 weeks' time from the date of notification of commencement of works for this section.

The condition survey of tiled or rendered area shall include, but not limited to the followings:

(a) Closely examine the complete area of external tiling/render for visible defects.
(b) Sound all areas with hammers to ascertain extent of defects .
(c) Record type, size and location of defects.
(d) Removal of small areas of loose or potentially dangerous materials.
(e) Reporting of large areas of loose or potentially dangerous materials to the Project Manager's Representative.
(f) Provide record photographs of individual blocks and defects encountered.
(g) Provide reports of each block in the format as directed.

9.2 Access

The survey work is to be carried out using scaffolding. The Contractor shall demonstrate that such person that he may employ have received the necessary training and instruction to carry out such works.

9.3 Hammer Tapping

Works shall be carried out by trained technicians with adequate safety look outs at ground level.

Prior to commencement of work, the technicians should be instructed in regard to the potential hazards arising from the works, protective measures to be implemented to prevent injury, damage etc. to the public, tenants or the workmen and the techniques to be used for tapping and recording.

Hammer tapping to all areas of external tiling/render by an approved means of access at a maximum of 600 mm centers each hammer tap. The contractor shall ensure that the technicians are properly trained and check the surveys for accuracy.

9.4Hammers etc.

Hammers for sounding purposes shall be of metal, in one piece and of an approved type, capable of detecting areas of debonding in the finishes of up to 50 mm. Hammers and other tools/equipment shall also be fitted with a lanyard securely attached to the Project Manager.


9.5Recording of Defects

A report sheet to an approved format shall be used to record areas of defects. A copy of the report sheet is to be handed to the Project Manager's Representative not later than the end of the following working day. The report sheets are to clearly indicate the extent and severity of the defects encountered.

Defects in addition are to be indicated where encountered on the face of each building using a marking system approved by the Project Manager. The marking of defects using spray paint with the exception of complying with the requirements of Clause 28.06 (General Specification of Hong Kong Housing Authority) is not to be undertaken without the approval of the Project Manager.

Following the completion of survey work for each building, a survey summary report to an approved format is to be completed. The survey summary report is to be submitted to the Project Manager not later than 7 days following the completion of survey work for each individual building.

Random testing will be carried out to verify the findings of the reports. If the latter is found unsatisfactory, the contractor must carry out survey again and submit a revised report to the Project Manager for approval. All cost incurred therein shall be borned by the Contractor.

9.6Loose Material

Small areas of loose material (generally not exceeding 0.25 square metres) which are likely to pose a danger should they become dislodged are to be removed. Records of small areas removed are to be submitted to the Project Manager's Representative not later than the end of the following working day for confirmation. Larger areas to be marked on the building by the use of spray paint or other approved materials, immediately reported to the Project Manager's Representative and highlighted in the daily report sheets for further action. Large areas may be required to be removed as directed by the Project Manager.

The perimeter of areas removed shall be sealed immediately after removal using an approved mastic sealant.

Catch nets or similar approved means are to be provided to safely contain any removed material and the Contractor is to have in attendance on the ground, personnel to ensure the safety of the public, where the removal of such loose material is likely to pose a danger.

SECTION 10.0 EXTERNAL ELEVATION CLEANSING

10.1 The application technique of chemical cleansing to the building facade should be carried out as follows and recommended and directed by the Contractor. And the application procedures should be strictly supervised and monitored by the Contractor competent and experienced foreman. The information of the chemical cleansing agent should be submitted for the Project Manager's prior approval.

10.2 The wall is first sprayed with water. Wetting is to avoid excessive penetration of chemicals and soil into the surfaces of the building. Pre-wet the area to be cleaned with clean water. A convenient way of achieving this is by using a low-pressure water lance.

10.3 The chemical cleaners are then spreaded over the damp surface by a brush or
by using a low-pressure spray. The application should be even and planned between architectural features (for example, plinth to cornice or between internal angles of buttresses).

10.4 The coverage rate should be in the order of 1 liter per 3.7 square metres of
surface area.

10.5 The contact period with the surface will vary depending on the amount and type of soiling and on the ambient temperature. The contact period will only be allowed to leave for 5 to 15 minutes on the tiles, depending on the temperature.

10.6 Repeated application may be necessary. The cleansing material must never be
allowed to dry on the surface.

10.7 Finally, the cleaners and dissolved soil are removed by thorough rinsing at the correct time with a low pressure jet of clean water. At this stage, the use of a neutralizer may be used before the final water rinse.

10.8 Rinsing for 4 minutes per square metre is recommended ω a minimum time, with extra attention being paid to water traps, such as cills and strings, or weathered joints. The rinsing water must not be allowed to accumulate on such traps as when the water evaporates, the acid concentration will increase and while deposits of colloidal silica may be left behind. The foaming agent could identity the present of any resident acid.

10.9 General procedure for protecting the building structure, building environment ,
street & public and the cleaning equipment must be taken, but particular care must be taken to protect contract personnel and the public from spillages or drift.

10.10 First-aid boxes containing sodium gluconate gel or similar artides must be
kept on site.

First-aid treatment for acid burns includes the following procedures:

(i) Burns must be washed immediately with copious amount of clean water for at least one minute, followed by rubbing calcium gluconate gel into and around the burned area, with clean fingers.

(ii) The gel should be rubbed in continuously until 15 minutes after the
pain has subsided and hospital treatment must follow.

(iii) If the gel is not available, washing must continue until it is.

(iv) Eyes which have been affected should be irrigated with isotonic saline
or clean water for at least 10 minutes.

10.11 All cleaning equipment tubes or boxes must be securely capped to avoid the
trapping acid or acid vapor.

10.12 Use a proprietary or tailor-formulating pre-diluted form of chemical cleaner: the concentration of acid must be known and displayed on the container (between 2 and 15%). Do not store the industrial-concentrated acid (which may be over 70%) on-site dilution, keep the acid in a secure store and adequately labelled.

10.13 Pre-wet the area to be cleaned with clean water. By using a low pressure water lance is to provide a damp surface, on which the chemical will spread. Thorough wetting will limit the activity of the chemical of the soiled face.

10.14 Apply the acid by brush to the damp surface, or by using a low-pressure spray.
The application should be even and planned.

10.15 The importance of thorough washing off at the correct time has been paid more
attention.

10.16 The cleaning equipment, working platforms, swing chair or cradle must also be washed off thoroughly after each rinsing of the building and the cleaning equipment tube capped and also checked.

10.17 Subsequent applications of the chemical must follow the same procedures. At
least half an hour should elapse before a second application.

10.18 Where applicable the Contractor may provide all swing chairs for the execution of the work. All elements and necessary materials in connection are to be good quality and adequate for the purpose for which they are used.

10.19 The Contractor shall ensure that all swing chairs or cradle and their supporting means are of adequate strength and stability to carry the loads to be sustained and that all materials used in their construction are sound.

10.20 The Contractor shall make good any damage caused to the walls, floors and other surfaces during sue, erection, dismantling, transportation and relocation of the swing chairs or cradles.

10.21 Detailed as-built drawings shall be provided by the Contractor on the supporting mechanism, fixing and, stabilization means in connection with the installation and operation of the swing chairs or cradles.

10.22 Temporary electricity power supply may be connected by the Contractor from
appropriate source on site as approved by the Project Manager.

10.23 Each workman on swing chair or cradles during the execution of work shall be
connected with appropriate independent safety line.

10.24 The Project Manager may from time to time require additional safety measures as directed or recommended by the Labour Department or through its representative officials on site which will be at the Contractor own expenses.

11.0 STEEL WORKS OF VERTICAL SURFACE

11.1Surface Preparation

All Steel works shall be cleaned thoroughly by approved power tools to the SSPC-SP3 standard or hand tool clean to the standard of SSPC-SP2 to remove all rust, contamination, excessive roughness, dirt, oil and foreign materials.

11.2Painting Works

11.2.1 Three Layers of coating shall be applied to the metal surface in the following
order:

a. One touch-up of Amerlock 400 High Solids Epoxy coating or equivalent-
Oxide red, touch-up to full film thickness.
b. One touch-up of Amerlock 400 High Solids Epoxy coating or equivalent-
Peral Grey, applied at a dry film thickness of 125 microns
c. One touch-up of - PSX 700 Engineered Silocane Coating or equivalent-
Grey, applied at a dry film thickness of 125 microns.

11.2.2 The contractor shall submit the color sample boards for the Surveyor's
approval prior ω before the ordering of topcoat paint.

11.2.3 The contractor shall submit an inspection form to Employer for inspection and
approved before application of each layer of paint. Immediately prior to the
application of paint all loose particles, dust and debris shall be removed.

11.2.4 Temporary disassembly and its associated protection works of the clamps/ brackets/ ducting systems are required for painting pf the member of steel frame. Special care shall be taken during these procedures and the clamping/ ducting system shall be reinstated to the original condition afterward.

11.2.5 Application of coating by method of spraying is not allowed to be used.

11.2.6 The contractor shall provide a check meter or instrument for checking of the thickness of applied coati paint. If the thickness of any layers of the applied coats cannot meet the specified thickness listed in clausesl1.4.1, the contractor is required to removed the applied coating and reapply the coating to meet the specified requirements.

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