Alternative Site at KOM, Muscat
Volume IV
Architectural Specification
Central Bank of Oman
Central Bank of Oman
Alternative Site at KOM, Muscat
Volume IV
Architectural Specification
May 2011Report no. 210206 Issue no. 0 Date of issue May 2011 Prepared HMB Checked SVHK
Table of Contents
1 General Information 6
1.1 Project Details 6
1.2 Associated Contracts 7
1.3 General Requirements 7
1.4 ‘As-Built’ Drawings and Information to be provided 11
1.5 Manufacturers’ Data 12
1.6 Site Meetings 13
1.7 Warranties & Guarantees 14
1.8 Manufacturer’s Recommended Spares 15
1.9 Substantial Completion and Handover 15
1.10 Period of Maintenance 19
2 Plasterwork and Floor Screeds 21
2.1 General 21 2.2 Materials 22 2.3 Execution 23 3 Membrane Roofing 29 3.1 General 29 3.2 Materials 30 3.3 Execution 32 3.4 Protection 34
4 Carpentry and Joinery 35
4.1 General 35
4.2 Materials 36
4.3 Execution 39
5 Metal Doors 46
5.2 Materials 47 5.3 Execution 47 6 Wooden Doors 49 6.1 General 49 6.2 Materials - Doors 50 6.3 Execution - Doors 52
7 Aluminium Doors & Windows 54
7.1 General 54
7.2 Relevant standards 54
7.3 Materials and Performance 55
7.4 Execution 57 7.5 Automatic doors 58 8 Ironmongery 59 8.1 General 59 8.2 Materials 60 8.3 Execution 60 9 Glazing 62 9.1 General 62 9.2 Materials 62 9.3 Execution 64 9.4 Structural Glazing 68 10 Ceramic Tiling 69 10.1 General 69 10.2 Materials 70 10.3 Execution 72 10.4 Special Requirements 76
11 Hard Floor Tiling 77
11.1 General 77 11.2 Materials 77 11.3 Execution 79 12 Concrete/Screed Hardener 81 12.1 General 81 12.2 Materials 81 12.3 Execution 82
13 Suspended Ceilings 83
13.1 General 83
13.2 Materials 84
13.3 Execution 86
14 Raised Access Flooring 89
14.1 General 89
14.2 Materials 89
14.3 Installation 90
14.4 Inspection and Testing 91
15 Demountable Partitions 92 15.1 Scope of Work 92 15.2 Standards 92 15.3 Submittals 92 15.4 Materials 92 15.5 Installation 93 16 Painting 94 16.1 General 94 16.2 Materials 96 16.3 Execution 98 17 Carpeting 104 17.1 General 104 17.2 Materials 105 17.3 Execution 106 18 Stone Cladding 108 18.1 General 108 18.2 Materials 108 18.3 Execution 109 19 Metal Cladding 111 19.1 General 111 19.2 Material 111 19.3 Execution 112
20 Joints, Sealants and Joint Covers 113
20.1 General 113
21 Sanitary Ware 116 21.1 General 116 21.2 Materials 116 21.3 Fixing 116 21.4 Sealant 117 21.5 Protection 117
21.6 Inspection and Testing 117
22 Wall Guard Systems 118
22.1 General 118
22.2 System Description 118
22.3 Submittals 119
22.4 Manufacturer 119
22.5 Execution 120
23 External Work – Ground Finishes 122
23.1 Scope 122
23.2 General 122
23.3 Materials 124
23.4 Pre-cast Concrete Paving Blocks 127
23.5 Workmanship 131 24 Flood Gates 136 24.1 Scope 136 24.2 General 136 24.3 Products 139 24.4 Execution 141
25 Vertical Transportation Systems 144
25.1 Passenger Lifts and Goods Lift 144
25.2 Execution 175
26 Asphalt Paving 178
26.1 General 178
26.2 Asphalt Paving 178
26.3 Concrete Kerbs 178
27 Through Coloured Render 181
28 Carpets 183
28.1 General 183
28.3 Execution 184
29 Flagpoles and Flags 186
29.1 General 186 29.2 Materials 186 29.3 Execution 186 30 Carpark shades 187 30.1 General 187 30.2 Materials 187 30.3 Execution 187
31 Epoxy Resin Flooring 188
31.1 General 188
31.2 Material 188
31.3 Preparation Of Substrates 189
31.4 Laying Flooring 190
32 Anti- Static Vinyl Tiles 192
32.1 General 192 32.2 Material 192 32.3 Laying Flooring 193 33 Porcelain Tiles 194 33.1 General 194 33.2 Material 194 33.3 Execution 196
1
General Information
1.1 Project Details
1.1.1 General
The project comprises of the following works:
• Construction of new Office Building comprising of 6 floors (Basement, Ground floor, 4 typical floors) in accordance with the drawings and specifications.
• The construction of the basement raft and the retaining walls all around along with the access ramp and the water tank structure have been constructed in package .
• Construction of Security Buildings, ETS building and fenced compound with services buildings.
• Construction of external works including boundary wall – partly K4 rated, parking and access roads, etc.
• Modification to existing road around the plot for entry and exits.
1.1.2 Location
The project site is located within the premises of Knowledge Oasis Muscat at Al Khod Seeb.
1.1.3 Site Conditions
A copy of the Site Investigation Report is available for review at the Engineer’s office. It is a requirement that all Tenderers shall read the report and acquaint themselves fully with its contents. No consideration shall be given to any claims arising from non-acquaintance of the site conditions.
The Main Contractor will be responsible for all making-up of ground to
finished levels where required including compaction and testing of the made up ground.
The principal foundation system for the building will be concrete, bored cast-in-situ pile foundations under the columns in accordance with the
recommendations of the Site Investigation Report and strip foundations or ground slab thickening under the walls.
All foundations and basements are to be protected as shown on the drawings. All basement areas are to be fully tanked as detailed on the drawings.
1.2 Associated Contracts
The present tender includes the general construction work, complete with most finishes, fittings and electro-mechanical engineering installations, specialist security and Data Centre requirements and associated external work.
1.3 General Requirements
The following contains a description of general requirements to be part of the scope of work.
These works shall be deemed to be included in the Contractor’s Preliminaries.
1.3.1 Signboards
Supply and fix project sign board(s) in compliance with the requirements of KoM at the entrance to the site. Prepare layout sketch for the Engineer’s approval prior to fabrication and erection.
1.3.2 Notices and Permits
It is the Contractor’s responsibility to obtain all Authority approval/permits required for the execution of the entire project work.
1.3.3 Use of the Site
The work shall be carried out to cause minimum disturbance to the operation of the adjacent roads and adjoining buildings. The Contractor shall within one week from the Instructions to Commence submit a site plan including all site facilities, stores, cranes and stationary equipment for the Engineer’s approval.
1.3.4 Consultant’s Site Facilities
Provide site facilities for the Consultant in accordance with the schedule in the preliminaries section and Appendix A hereto. The site facilities shall be maintained and serviced for the duration of the project.
1.3.5 Record Photographs
The Contractor shall provide progress photos, on a monthly basis. Three sets of photos shall be submitted monthly and shall remain the sole property of the Client.
The Contractor shall not use any photos for other purposes without the Client’s written consent.
The Contractor should note that photography in the area is strictly controlled and that improper use of cameras could lead to difficulties with the Security Forces.
1.3.6 Contractor’s Supervision
The Contractor shall provide a suitable supervision team full time on site. The Contractor’s Engineers shall have relevant successful experience from similar projects.
Qualifications and experience details of the main members of the team are to be submitted with the tender for the Engineer’s approval, and interviews with the Engineer are to be conducted prior to approval of any staff.
1.3.7 Standard of Workmanship & Materials
All work shall be executed with the best workmanship and to accepted standard practices. Relevant British Standards and other Codes of Practice shall be followed unless otherwise indicated in accompanying drawings/specifications or where otherwise directed by the Engineer.
Reference to British Standards which shall refer to the edition current at the time, shall not preclude the use of materials from sources where other standards apply, but no materials to be incorporated in the works shall be in any respect inferior to those which specifically comply with the British Standard. Should the Engineer discover on the works any material other than those approved, he may order their removal from the site, including the demolition of any works already built with these materials.
All proprietary materials incorporated in the works shall be fixed or applied strictly in accordance with the Manufacturer’s instructions.
Where proprietary materials are referred to in this specification the intention is to establish the type and quality of materials required. Similar materials of equal and alternative manufacture may be offered in substitution, for approval by the Engineer. The Engineer has no obligation to approve the alternatives offered by the Contractor.
All materials to be used in the permanent works shall be stored on racks or supports, in bins, under cover etc. as appropriate to prevent deterioration or damage from any cause whatsoever. Storage arrangements for specific materials shall be as approved by the Engineer.
Where materials, products and workmanship are not fully specified, they shall be suitable for the purpose of the works stated in or reasonably to be inferred from the Contract Documents, and in accordance with good building practice, to the satisfaction of the Engineer.
Approval of all products or materials specified is required. The Contractor shall submit samples or other evidence of suitability to the Engineer at least 21 days before the approval is required. The Contractor shall not confirm orders or use materials until approval has been obtained. Delays due to non-submission of samples or inadequate support literature shall be the sole responsibility of the Contractor.
Approved samples shall be retained on site for comparison with products and materials used in the works and shall only be removed when no longer required by the Engineer.
Where samples of finished work are specified, the Contractor shall obtain approval of stated characteristics before proceeding with the works and shall retain approved samples on site for comparison with the works. Samples which are not part of the finished works shall be removed when no longer required by the Engineer.
1.3.8 Inspection and Testing
Whenever considered desirable the Engineer or his representative may visit the source of supply or Manufacturer’s work areas to test the materials or supervise their production. Materials shall be tested before leaving the supplier’s
premises or Manufacturer’s works as well as after delivery to the works. The Contractor shall allow reasonable time for the Engineer to make
arrangements for inspection and give permission for dispatch to the site. Delay to the works arising from late notification of such details will not be accepted as reason for delay in completion of the works.
All Manufacturer’s certificates of tests, proof sheets, mill sheets etc. (in English language) showing that the materials have been tested in accordance with the requirements of the appropriate British Standards, other relevant standard or this specification, shall be supplied free of charge, if required by the Engineer.
1.3.9 Working Drawings (Shop Drawings) 1.3.9.1General Requirements
Prepare working drawings for all services, assemblies and pre-cast/fabricated components in accordance with this section and relevant sections of the Services Specification.
Submit to the Engineer for approval four copies of all working details and drawings and also supply two copies for the use of the Employer and other interested parties.
These drawings must be submitted as soon as possible after the contract is awarded to give ample time for all concerned to study and comment thereon prior to the programmed commencement date for the related works.
Latest submission shall be 3 weeks before commencement date for the work. Carefully check the work described on working drawings for all clearances, field conditions, maintenance of architectural conditions and proper co-ordination with all trades on the job. To this end, during production drawing stage, co-ordinate drawings of all other trades that might interfere with the proper installation of the work.
Any unresolved conflict between trades shall be referred to the Engineer.
1.3.9.2 Details to be shown
Services and equipment layouts shall be detailed on the drawings, showing the exact method of installation and clearly illustrating components to be used in making of all connections.
General layout drawings shall be drawn to 1:50 scale, unless agreed otherwise with the Engineer. Toilet piping layout, details and hangers, cleanouts, distribution boards, power and control panels, methods of fixing of all equipment, including pipes and conduits, detailed cross sections of service ducts, etc. are to be drawn to 1:10 scale.
Prepare schedules and drawings showing precise details of holes in concrete, block work, etc. bases, frames or support required and the like. The schedules shall show in-detail the builder’s work required to be performed by all other trades for the services installations.
These drawings and schedules, in an approved form, must be submitted to and properly approved by the Engineer before any structural work requiring holes or other modifications is constructed.
1.3.9.3 Approval Procedures
Submit all drawings as prescribed hereunder. All drawings submitted for approval shall be supplied in the form of prints and signed by a principal of the Contract. After approval, the negatives will be signed by the Engineer and returned to the Contractor who shall then provide four sets of prints to the Engi-neer.
Signed and approved drawings will not be departed from unless a signed variation or omission certificate is issued in writing by the Engineer. Drawings returned to the Contractor for alteration or amendment shall be re-submitted to the Engineer for approval.
Amended or altered drawings shall show the nature of the amendment or alteration in a revision block on the drawing, together with the revision number or letter and the date of the revision.
The Engineer’s approval of working details and drawings will not relieve the Contractor of his responsibility for errors and incorrect setting out. The Engineer’s approval is only general and not intended to serve as a check and does not relieve the Contractor from furnishing the materials and performing the works as required by the Drawings and Specifications.
Should the Contractor proveto beunable to produce satisfactory “Working Drawings” or be unable to produce drawings to conform to the progress of the work, the Engineer reserves the right to take whatever steps are necessary to have drawings undertaken by others and debit the cost of the same to the Contractor’s account.
Any decision taken by the Engineer to have working drawings produced elsewhere will not relieve the Contractor of his contractual obligations and the Contractor must provide to the Engineer all necessary details, physical
dimensions, descriptive literature, etc. of all equipment to be incorporated on drawings within 10 days of a request from the Engineer.
1.4 ‘As-Built’ Drawings and Information to be provided
1.4.1 General Requirements
Arrange to keep on site a full set of drawings showing the progress of the Works, which must be kept up-to-date.
Keep a record as the work proceeds of any work installed not in accordance with the drawings.
Upon completion of the Works, prepare a completely new set of drawings for the work as executed and submit same in duplicate to the Engineer. Submit two sets of diskettes (AutoCAD), and two copies of all drawings duly marked ‘As-Built’ clearly defining all locations, depths, shapes and dimensions of all permanent works executed. These shall include, but not necessarily be limited to Architectural, Structural, all Services and purpose-made components and assemblies.
The words “AS BUILT” shall be clearly indicated on all drawings adjacent to the title block. Each set of prints shall be bound into the Operation and Maintenance (O & M) manuals, with each drawing separately folded and contained in plastic sleeves.
There will be no entitlement for any extra payment or extension of time for the correction, preparation and supplying of the above mentioned drawings and information. The completion certificate for the work will not be issued until the Service Manuals and ‘As-Built’ Drawings are approved.
1.4.2 Service Requirements
For Mechanical and Electrical plant and equipment, provide the following information to be incorporated in the O & M manuals:-
1. Detailed Design Conditions & Criteria and schedules of the Plant as actually installed.
2. Instructions for the Maintenance and Overhaul of the Plant installed. 3. Recommendations for consumable supplies, e.g. packings, lubricants, etc. for
the Plant installed.
4. Drawings showing the internal construction of the major items, with parts listed and reference numbers for ordering spares.
5. Complete assembly drawings of machinery and ancillary plant showing all pipe connections and fittings.
6. General arrangement drawings showing all equipment, cabling, tray-work, etc. 7. Detailed arrangement of any conduit work buried in floors, walls or
ceilings, in any buildings or concrete works. 8. Detailed wiring diagrams of the main circuits.
9. Diagrams of connections between all items of equipment (e.g. main and auxiliary switchboards, motors, starters, batteries, meters, instruments,
relays, electronic and allied equipment, etc., with component values and types suitably marked thereon).
There will be no entitlement for any extra payment or extension of time for the correction, preparation and supplying of the above mentioned drawings and information. The completion certificate shall not be issued until all service manuals and ‘As-Built’ Drawings are approved.
1.5 Manufacturers’ Data
Manufacturers’ performance data and certified factory drawings of apparatus, giving full information as to capacity, dimensions, materials and all information pertinent to the adequacy of materials and equipment shall be submitted for approval.
Manufacturer names, sizes, catalogue numbers and/or samples of all materials shall be submitted for approval.
Submittals and working drawings should, as far as possible be complementary so that drawings and submittals can be cross-checked.
Ordering details of material submitted for approval must be accompanied by relevant drawings, technical data, catalogues and samples. Where data certified drawings or other required information is not available until after orders have been placed, the Engineer will give provisional approval conditional on all requested drawings and information being supplied to the Engineer found to be acceptable by him.
Ensure that all necessary information is supplied to the Engineer in accordance with the progress of the work.
1.5.1 Preliminary Programme (Clause 14)
A preliminary outline programme for carrying out the works shall be prepared by the Contractor and submitted with the Tender. Within 14 days after the acceptance of the Tender, prepare a final programme for carrying out the works and submit copies of the programme to the Engineer for approval.
The programme shall be sufficiently detailed to show in itemised graphic bar chart form all trades and activities necessary for the completion of the structural works. The programme shall identify a “critical path” of activities essential for timely completion of the works which shall define the earliest and latest possible dates for commencement and completion of each activity.
1.5.2 Detail Programme (Clause 14)
The final programme shall be prepared by the Contractor and submitted within six weeks after acceptance of the Tender. It shall be accompanied by a
comprehensive materials ordering schedule showing latest dates for approval of proposed materials in order to meet the requirements of the programme. Allow at least six weeks for review and approval of material approval
submittals: on no account will delays to the work be accepted where caused by failure to obtain approvals of materials from the Engineer.
The material ordering schedule shall list the following information: i. Schedule of Rates/Bills of Quantities reference.
ii. Material Description.
iii. Approval Date (Programme). iv. Approval Status.
v. Ordering Date (Programme). vi. Ordering Status.
vii. Delivery Date (Programme). viii. Delivery Status.
ix. Installation Dates (Programme). x. Installation Status.
The preliminary and detail programmes shall be accompanied by details of labour force monthly loadings for each trade, including subcontractors and supervisory staff.
The Working Programme shall show the periods for installation, inspection, testing and commissioning the electrical and mechanical plant and equipment, and periods allocated for general snagging and rectification of defects. Programme to be prepared and submitted within 2 weeks.
Allow at least 1 (one) week for review and approval of Material Approval Submittal.
1.5.3 Programme Priorities
The programme of works shall include the following works as immediate priorities at the outset of the construction period:
A site survey and preparation of site survey drawing at 1:200 scale to verify the information on the site survey drawing included in the tender documents.
1.5.3.1 Establishment of Acceptance Standards
Where there are a number of similar rooms or similar elements in the project, then one of these rooms or other elements should be selected to be completed in advance of others in order that the standard of finish, or any other matter, may be commented upon. Thereby, a standard is to be set on which future
inspections of similar rooms or similar elements will be based. Such areas should be programmed separately.
1.5.4 Shop Drawing Production Programme
The detailed production programme shall be accompanied by a working drawing production programme.
Submission of such programme shall not relieve the Contractor of any of his duties or responsibilities under the Contract.
1.6 Site Meetings
Attend with adequate representation the site meetings and all other meetings to which the Engineer has given instruction to attend.
Inform and present to attend meeting(s) representative(s) for sub-contractors, suppliers, etc., if so requested by the Engineer.
The Engineer will chair the meeting and be responsible for the preparation and distribution of Minutes.
Hold co-ordination meetings with sub-contractors two days prior to the Site Meetings to ensure accurate reporting on progress, information, etc. Submit the following information, in writing, one day prior to each site meeting: i) Progress report showing percentage completion scheduled and actual
percentage completed for each activity of the programme. ii) Plant and Labour reports for the month.
iii) Minutes of Contractor’s Co-ordination meeting. iv) Schedule of Information requirements.
v) Updated Material Ordering Schedule
vi) Records of daily temperature, humidity and rain-fall vii) Record of Site Instructions issued since previous meeting viii) Record of Payments
ix) Estimates of anticipated variations and instructions if previously requested by the Engineer.
1.7 Warranties & Guarantees
All equipment and installations supplied under a manufacturer’s warranty shall be covered by warranty for the entire maintenance period and such additional periods as outlined below.
The warranties are specifically required for the following elements:-
♦ Roof Waterproofing 10 years
♦ Anti-Termite Treatment 15 years
♦ Ironmongery 5 years
♦ Window & glazing installation 10 years ♦ Waterproofing membranes 10 years ♦ Chiller compressor and coating 5 years ♦ External Paint System 5 years ♦ Internal Paint System 5 years
♦ Marble/tile finishes throughout ♦ Stone cladding fixing system ♦ External Metal Cladding system
10 years 10years 10years
Sample form of warranty shall be submitted with the tender. The final original certificate shall be included in the O & M Manuals.
1.8 Manufacturer’s Recommended Spares
Provide all tools, keys etc. together with spare parts and consumable stores sufficient for operating all services installations for a period of one year commencing from the date of the Completion Certificate all in accordance with manufacturer’s recommendations and the Engineer’s approval.
1.9 Substantial Completion and Handover
1.9.1 Definition
“Substantial Completion” is that stage in the execution of the work under the Contract when:
• the Works or a separable part of the Works, as the case may be, are complete except for minor omission and minor defects;
• which do not prevent the Works or that separable part of the Works from being used for its intended purpose, and
• in relation to which the Engineer determines that the Contractor has reasonable grounds for not promptly rectifying them, and
• rectification of which will not prejudice the convenient use of the Works or of that separable part of the Works, and
• those tests which are required by the Contract to be carried out and passed before the Works or the separable part of the Works, as the case may be, are handed over to the Employer have been carried out, documented and passed, and
• Such Documents and other information required under the Contract which, in the opinion of the Engineer, are essential for the use, operation and maintenance of the Works have been supplied. This includes As-Built Drawings and Operation & Maintenance manuals.
1.9.2 Handover Programme
As the works approach substantial completion, submit to the Engineer a
programme outlining the main events leading up to the Final Handover Meeting to ensure that the handover arrangements proceed efficiently.
The programme shall include the following events:- 1. Preliminary snagging by Contractor.
3. Final snagging inspection by Engineer/Contractor.
4. Testing and commissioning of electrical and mechanical plant and equipment on site.
5. Familiarization of Employer nominated operatives with the electrical and mechanical equipment.
6. Substantial Completion Inspection of the Works by Employer/Engineer including all required submissions of manuals, drawings, spare parts, etc. 7. Issue of the Certificate of Completion.
8. An inspection or series of inspections (as demanded by the size and nature of the project) by Engineer and relevant technical experts to obtain clearance for occupation of the Works by the Employer.
9. Final Handover Meeting at which the keys are handed over to the Employer for occupation of the site.
1.9.3 Documentation for Testing and Commissioning
By the end of mobilization period, submit formats for the contents of all electrical and mechanical Testing and Commissioning Schedules and the layout and contents of all electrical and mechanical Testing and Commissioning Certificates. Testing and Commissioning Certificates are to be signed by the Contractor and
countersigned as approved by the Engineer before issue. Certificates for electrical installations in buildings are to be in accordance with the ‘IEE Regulations - 15th Edition’.
The site commissioning and test results are to establish the optimum conditions for plant and equipment and form the basis for future condition monitoring. After items of electrical or mechanical plant or equipment have been tested and commissioned copies of each of the following shall be bound into the O & M Manuals:
1. Testing and Commissioning Certificates
2. Full site performance test result sheets and reports.
1.9.4 Familiarisation with the Works Programme
The Client’s staff responsible for operation and maintenance of the works after hand over, shall be given the opportunity of familiarization with the facilities including the documentation (in particular for the mechanical and electrical plant and equipment) in advance of the Handover Meeting.
1.9.5 Demonstration of Plant and Equipment
Demonstrate the operation, regulation and general maintenance of the plant and equipment and bear all costs relating to the familiarization (including the cost of any specialist training for particular equipment).
1.9.6 Draft Documentation
The following draft submissions shall be provided as early as possible in the construction period but no later than the scheduled time for familiarization with the Works:
1. One set of the Operation and Maintenance Manuals.
2. One copy of the priced list of breakdown spares (together with any special tools required) for one year operation and where appropriate also for five years operation as recommended by the Manufacturer.
3. One copy of the priced list of consumable spares (e.g. filters) and other consumables (e.g. chemicals for dosing water supply) for one year’s operation, as recommended by the manufacturer.
4. One set of prints of the electrical and mechanical As-Built Drawings. The Operation and Maintenance Manuals are required to describe the complete working system. It will not be sufficient to submit only the manufacturer’s literature for the component parts of the system, although such literature may form part of the manual. The As-built Drawings must include the modified infrastructure drawings where this is appropriate.
1.9.7 Submissions
Make the following submissions on or before the date of Substantial
Completion. The works shall not be considered Substantially Complete until all of these submissions have been made (draft manuals are not acceptable at this stage):
1. Three sets of the approved Operation and Maintenance Manuals. These manuals are to include detailed descriptions of the operation of the system, and are to explain the nature and frequency of the various routine
maintenance tasks.
These manuals must be suitable for use on site (i.e. plastic covers, based on A4 size, capable of being laid flat when opened, fully indexed). One copy of each of the approved Testing and Commissioning Certificates, site
performance test result sheets and reports, and the Testing and
Commissioning Schedules (as carried out) is to be included in each set of manuals.
2. An additional set of manuals for specialist equipment shall be supplied for the use of the specialist User.
Additional copies of operating instructions for individual items of equipment which can be adjusted by non-specialist users (room controls for A/C’s, fire safety procedures etc.) shall be provided for each item of equipment.
3. Three copies of the approved priced list of break-down spares (together with any special tools required) for one year operation and where appropriate also for five years operation.
4. One set of the breakdown spares (together with any special tools required) for one year operation and where appropriate also for five years operation. 5. Three copies of the approved priced list of consumable spares and other
consumables for one year operation.
6. One set of the consumable spares and other consumables for one year’s operation (actual delivery having due regard to shelf life where appropriate). 7. Three sets of the keys for all locks (including floor and ground master keys
where necessary), two sets of valve keys, and two sets of manhole cover lifting keys.
8. Three sets of prints of all the approved As-Built Drawings (the electrical and mechanical ‘As Built’ Drawings must be adequate for the operation and maintenance of the facilities).
9. Two sets of copy transparencies of all the approved As-Built Drawings to a standard suitable for photo reduction.
10. The original of all approved Testing and Commissioning Certificates (bearing the signature of the Engineer who witnessed the tests).
11. Three copies of an Asset Register for all electrical and mechanical plant and equipment requiring routine maintenance.
The Asset Register is to have the following items included in the schedules: a) Item reference number - to be assigned by Employer.
b) Description c) Rating d) Manufacturer e) Model number f) Total quantity
g) Unit cost - FOB at the time of purchase h) Purchase order no. - issued by the Contractor i) Identification and location:
i. quantity at a given location or in a facility ii. serial no. of the equipment where applicable
iii. tag number or title given to design on item or class of items (where applicable)
iv. location of facility j) As-Built Drawing reference.
1.9.8 List of Outstanding Work
a) Prepare three copies of the list of outstanding work. This list is to include all items which are still outstanding at the date of Substantial Completion, and which are to be finished by the Contractor during the Period of Maintenance in accordance with the programme set by the Engineer. Unless there is good reason for the contrary, it is expected that the
outstanding work would be satisfactorily completed within at least 28 days of Substantial Completion.
b) The items on this list must be relatively minor items of outstanding work or the making good of minor defects in the work already completed. Items of plant and equipment, any other items where the full Period of
Maintenance is required, are not to be included on this list, but shall be considered as work required to be completed before the issue of the Certificate of Completion. However, this does not necessarily preclude the certification of completion of stages as defined in Clause 48(2) of the Conditions of Contract.
c) Attention is drawn to the amendments to the Standard Conditions of Contract requiring the Engineer to set a programme for the completion of the outstanding work and the remedy on the Contractor’s failure to carry out such work within the set programme.
1.9.9 Completion by Stages
If there are any outstanding items of work of such a nature that a separate Maintenance Period is required, such items shall be included on a list of outstanding work, for each stage.
1.9.10 Final Handover Meeting
a) The final Handover Meeting is to enable the works to be handed over by the Contractor to the Employer for occupation of the site. At this meeting the keys are to be handed over to the Employer.
b) The Handover Meeting shall take place after all the necessary inspections have been completed after issue of the Completion Certificate.
c) The following parties shall be represented at the meeting: 1) The Contractor
2) The Engineer 3) The Employer
1.10 Period of Maintenance
1.10.1 Division of Responsibilities
routine maintenance and operation of the works, making good fair wear and tear, and any repairs not considered to be the liability of the Contractor (e.g. damage to the works by the User).
1.10.2 Rectification of Defects
a) The Engineer will inform the Contractor in writing of those minor defects for which the Contractor is responsible for making good. Non urgent repairs must be carried out within 10 days of notification to the Contractor or, if this not possible, within a programme to be set by the Engineer. b) Where there is not a need to have defects repaired immediately, then
depending on the number and importance of these defects, the Employer will group them so that the Contractor is called back to the Site to carry out the work as few times as possible. For most practical purposes it would be satisfactory to clear the outstanding defects at (say) three monthly intervals. Emergency repairs must be carried out immediately.
c) Keep a register of all requests showing the date of the request, and the date on which the work was satisfactorily completed.
1.10.3 Inspection Prior to End of Maintenance Period
By approximately one month before the end of the Maintenance Period, all outstanding items shall be completed, and a joint inspection will take place.
1.10.4 Notice by the Contractor
Inform the Engineer in writing as soon as all the outstanding defects have been remedied and the works have been satisfactorily completed and maintained in accordance with the Conditions of Contract.
The Engineer will inspect the works and reply confirming agreement or pointing out any defects that have still to be remedied prior to issue of the Maintenance Certificate.
2
Plasterwork and Floor Screeds
2.1 General
2.1.1 Scope of Work
This section of the specification covers all internal and external plasterwork including “render” and floor screeds.
The specification for roof screeds is included under section 7 - Membrane Roofing.
2.1.2 Relevant British Standards
Conform to the recommendations made by the following British Standards where applicable:
BS 12 : 1978 Ordinary and Rapid hardening Portland cement BS 890 : 1972 Building limes
BS 5492 : 1990 Code of Practice for internal plastering. BS 882 : 1992 Aggregate from natural sources for concrete BS 1202 Specification for nails
BS 8000 : 1989, Part 9 Code of Practice for cement/sand, floor screeds and concrete floor toppings.
BS 8000 : 1989, Part 10 Code of Practice for plasticizing and rendering BS 1199 : 1976 Sands for external renderings and internal
plastering with lime and Portland cement. BS 1369 : 1987 Metal lathing (steel) for plastering.
BS 4887 : 1986/87 Mortar admixtures
2.1.3 Co-ordination
Check and verify the positioning and fixing of all conduits or other similar items which are to be concealed by either plaster or render or screed. Ensure
that such items requiring testing have been satisfactorily tested and approved by the Engineer before plasterwork is commenced.
2.1.4 Material Storage
All branded materials are to be delivered to the site in their original packages bearing the trade names of the material concerned.
Cement, hydrated lime and similar materials shall be stored off the ground, under cover and away from all possible source of damp.
Store sand under clean conditions to prevent contamination by soil or other deleterious substances.
2.1.5 Shop Drawings
Submit shop drawings showing the position of all external wall render and movement joints for the approval of the Engineer.
2.1.6 Literature and samples
In the case of proprietary products submit comprehensive technical literature for the Engineer’s prior approval. When so requested by the Engineer, prepare samples of plasterwork and/or render for his approval.
Samples to be a minimum of 10m2 in area for rendered surfaces and complete at least 1m2 with the required finish.
2.2 Materials
2.2.1 Cement
Ordinary Portland cement complying with BS 12 : 1978
2.2.2 Lime
Comply with BS 890. Quicklime's to be slaked in a manner appropriate to their type. Non-hydraulic and semi-hydraulic limes may be used dry or preferably soaked to a putty 16 hours before use.
2.2.3 Sand for plastering/rendering
Comply with BS 1199. Sand to be hard, clean and free from deleterious matter likely to affect adversely the hardening, strength, durability of appearance of the plaster.
2.2.4 Fine aggregate (including sand) and coarse aggregate for screeds
Comply with BS 882.
2.2.5 Water
Clean potable water free from harmful matter and from any unusual proportion of dissolved salts. Sea-water or brackish water shall not be used.
2.2.6 Metal lath, corner/stop beads etc
Proprietary expanded aluminium or galvanised steel lath internally, stainless steel externally, with associated accessories.
Building paper shall conform to BS 1521 Class B. Steel lath to comply with BS 1369.
2.2.7 Mortar plasticizers
Mortar plasticizers shall comply with BS 4887.
2.2.8 Nails
Nails shall be clout headed galvanised nails to BS 1202.
2.2.9 Metal Lathing
Metal lathing for plastering shall be galvanised expanded steel complying with BS 1369.
2.3 Execution
2.3.1 General
All plasterwork shall be executed in a neat and workman-like manner all to the approval of the Engineer. Conform to the recommendations of BS 5492 in regard to plastering.
2.3.2 Screeds
a) Jointing, Setting out of Bays
Screeding under in-situ flooring shall be carried out in accordance with the general recommendations and BS 8203 & BS 8000, Part 9 in the case of resilient and hard flooring materials respectively.
Cement and sand screeds which are to be covered with linoleum, vinyl or other thin material shall be laid in strips approximately 3m wide. Other joints shall coincide with joints in the concrete base.
The fill-in bays in this system shall not be laid until the alternate bays have hardened.
b) Preparation
To ensure proper bond any laitance on the concrete base slab shall be removed by scrabbling. Remove all dust and completely clean entire surface of base slab and keep well wetted for several hours before laying screed/topping. Remove free water and then brush in cement slurry or prime as necessary and use a bonding agent in accordance with manufacturer’s recommendations. Intended method to be agreed with the Engineer prior to commencing work.
Cover any pipes, floor trunking etc. with a strip of heavy gauge expanded metal lathing or light gauge steel reinforcing fabric 500mm wider than the embedded item.
c) Granolithic Screed
Granolithic flooring finishes laid thicker than 40mm shall be laid in two courses of which the upper shall be at least 18mm thick. Both courses shall have the same mix proportions including water-cement ratio. The lower course shall be thoroughly compacted and the upper course then immediately placed on it. After topping has been fully compacted, trowel surface at least 3 times at intervals during the next 6 to 10 hours to produce a uniform hard surface, free from laitance and with as much coarse aggregate as possible just below the surface.
Form skirting and up-stands etc. by trowel or formwork as appropriate on well-keyed backgrounds to required thickness and profiles. Thoroughly bond to the floor layers and form neat angles and junctions.
d) Sand/Cement Screed
Floor screeds shall be mixed in the volume of 3 parts sand to 1 part cement by weight. They shall be finished flat and smooth with a wood float if required to receive a further finish. Screeds for carpet shall be finished flat and smooth with a steel trowel.
Generally screeds shall be laid in bays not exceeding 12 square metres and in strips not exceeding 4.5m in width and/or 15 square metres. Joint allocations to be approved by the Engineer prior to starting work.
Screeds should be laid to the thickness shown on the Drawings or to falls as shown for areas which drain. Where a level screed is required variation in level should be limited to ± 3mm under a 3m straight edge.
The cement-sand ratio shall be 1:3 by volume. If laid within three hours of the placing of the base, or lesser time in hot weather, the screeding shall be not less than 12mm and not more than 25mm thick.
The screed shall be brought to a smooth and even surface to the required levels. Where the screed is to be laid on a set and hardened concrete base the screed shall not be less than 40mm thick and the base shall be prepared as described in Sub-Clause (b).
Where the screed is not bonded to the base its minimum thickness shall be 50mm.
Screeds over 40mm thick shall be formed in fine concrete of mix proportions 1:1:5:3 cement-sand-coarse aggregate (10 mm maximum) and shall be brought to a smooth and even surface to the required levels.
Screeds less than 80mm thick, to be laid in one layer. For screeds over 80mm thickness lay in two layers, the first being not less than 20mm thick and the second being placed immediately after compaction of the first layer.
Compaction of screeds to be carried out by approved mechanical means. Areas inaccessible to such equipment may be steel trowel compacted and floated manually.
Bring surface to a smooth uniform finish free from defects and blemishes to provide a satisfactory surface to receive the floor finish required.
Where cement and sand screeds are to receive terrazzo, clay or ceramic tiles the screed shall be finished with a slightly rough finish to accept the cement paste and tiles.
Check levels to ensure compliance with the requirement of the Drawings. Permitted tolerance will be 3mm in 3000mm in any direction.
e) Consistency of Mixes - Water Cement
The water content of the mixes used for cement and granolithic finishes shall be the minimum necessary to permit spreading and compaction.
f) Service Penetrations
Pipes and/or conduits shall not be cast into the screed without the Engineer’s prior approval. Should they be required they must have reinforcement overlaid as described in part (b).
g) Laying
The screed should be laid while the slurry or bonding agent is still wet. Ensure that it is well compacted.
The screed should be cured by closely covering screeded areas with polythene sheeting as soon as the screed is set and keeping this in position for 7 days. The screed should be kept damp during the curing period and wetted whenever necessary to achieve this.
During laying of screeds all existing work should be adequately protected against spillage, staining or any other damage.
h) Curing
As soon as the trowelling is completed maintain the concrete in damp condition for at least seven days with waterproof sheeting well lapped and kept in close contact. Thereafter ensure drying out continues slowly; protect from heat or any other conditions that might accelerate the drying.
i) Monolithic Finish
Monolithic finish to concrete floor slabs shall comprise carborundum dust evenly sprinkled on whilst the concrete is still green at a rate of not less than 1 kg/m2 and lightly trowelled in before final finishing.
j) Bathrooms
membrane shall extend around all walls to a height of 150mm above finished floor level. The membrane shall be applied in accordance with the
manufacturer’s recommendations. A 10 year warranty shall be provided.
2.3.3 Plastering/rendering a) General
Plastering/rendering will be carried out in accordance with BS 8000, Part 10 and BS 5492.
Remove ridges and other imperfections from shuttered concrete surfaces before cleaning down.
All surfaces to receive plaster/render to be thoroughly clean and free from any extraneous material which would adversely affect the plaster/render bond. Roughen smooth surfaces to ensure a keyed bond to plasterwork.
Thoroughly wet block work, concrete and other similar surfaces before plasterwork is commenced to reduce suction.
b) Metal lath, corner/stop etc.
All plasterwork stop ends, junctions with other materials and corners to have appropriate metal stop and corner beads.
Expanded metal lath to be installed where shown on the Drawings or as instructed on site by the Engineer. Provide such reinforcement to cover all construction joints, electrical conduits and service pipes running within walls. Metal lathing shall be fixed with galvanised steel staples with joints lapped 40 mm and tied with galvanised or stainless steel wires. The long way of the mesh should be at right angles to the supports. The slope of the strands should be all in one direction which for vertical work should be inwards and downwards.
c) Plaster/render mix proportions
All materials used for plasterwork shall be proportioned by volume by means of gauge boxes as follows:
Internal plastering : 1 : 1 : 6 (Cement:Lime:Sand) External rendering : 1 : 3 to 4 (Cement : Sand)
Note:
Lime putty may be added if required to improve workability but to a proportion not exceeding ¼ of that of cement by volume.
2.3.4 Mixing of plaster/render/screed
Except where hand-mixing of small batches is approved by the Engineer, mechanical mixers of an approved type shall be used for the mixing of plaster. Caked or lumped materials shall not be used. Mechanical mixers, mixing boxes and tools shall be cleaned after mixing each batch and kept free of plaster from previous mixes. Plaster shall be thoroughly mixed with the proper amount of
water, uniform in colour consistency. Re-tempering will not be permitted and all plaster which has begun to stiffen shall be discarded.
Hand mixed plaster shall be first mixed in the dry state being turned over at least three times. The required amount of water should then be added and the mix again turned over three times or until such times as the mass is uniform in colour and homogeneous.
Plastering mix containing self-setting materials shall be used up within the recommended working time for the mix concerned. Mixes containing cement shall be used up within two hours of the first contact of the cement with water. All material remaining after this period shall be discarded.
2.3.5 Handling and Storage
Metal lathing shall be stored in dry conditions and protected from damage.
2.3.6 Mixing
Hand mixed plaster shall be first mixed in the dry state being turned over at least three times. The required amount of water should then be added and the mix again turned over three times or until such times as the mass if uniform in colour and homogeneous.
Plastering mixed containing self-setting materials shall be used up within the recommended working time for the mix concerned. Mixes containing cement shall be used up within two hours of the first contact of the cement with water. All material remaining after this period shall be discarded.
2.3.7 Application of plaster/render
Unless indicated otherwise on the Drawings the thickness of plaster/render shall be as follows:
Internal walls 2 coats, total 15mm thick
Exposed Internal ceilings, soffits 2 coats, total 12mm thick
External render 2 coats, total 20mm thick
Carry out a sample for approval of each type of render on a suitable wall of approximately 10m2, including 1m2 with a final finish, as a test panel for approval before continuing the operation.
2.3.8 Curing of plaster
Allow adequate ventilation to remove excess moisture from the plaster and keep it moist in accordance with the recommendations of BS 8000, Part 10 for curing; do not allow the render to dry out too rapidly.
2.3.9 Defects in plaster/render
Defective areas of plaster/render to be carefully cut out to rectangular shape, using sharp chisels and taking care not to loosen adjacent material, the edges undercut to form dovetail key; apply bonding agent and allow to cure, re-plaster in accordance with the specification, allowing adequate time for drying
3
Membrane Roofing
3.1 General
3.1.1 Scope of work
Supply and installation of roof screed, protected waterproof membrane, insulation and protection for flat roofs.
3.1.2 Relevant Standards
Conform to the recommendations of the following British Standards where applicable:
BS 1470 : 1987 Specification for wrought aluminium and aluminium alloys for general engineering purposes.
BS 6229 : 1982 Code of practice for flat roofs with continuously supported coverings.
BS 8000 : 1989, Part 4 Code of Practice for waterproofing.
3.1.3 Submittals
Submit to the Engineer for his approval at least 60 days prior to use, proposals for the complete roofing systems together with full specifications, technical literature and samples.
Evidence must be provided of three successful installations of a similar nature which are at least ten years old.
The roofing system is to be approved in writing by the Engineer before commencement of the work, and the work is to comply in all respects with the approved specification.
3.1.4 Co-ordination
Check and verify the positioning and fixing of all conduits and other items which are to be concealed or laid within the screed thickness. Ensure that such items requiring testing have been satisfactorily tested and approved by the
3.1.5 Workforce
All roofing works are to be carried out by competent operatives skilled in this particular work.
Roof membrane shall be applied by an approved specialist subcontractor.
3.1.6 Guarantee
Completed waterproof membranes shall be guaranteed for a period of not less than ten years from the date of contract completion. Should any damage occur to the building or its contents as a result of faulty materials or workmanship, the Contractor shall make good such defects to the satisfaction of the Engineer.
3.2 Materials
3.2.1 Cement
Ordinary Portland Cement complying with BS 12:1978, or Omani Standard No. OS 07.
3.2.2 Fine Aggregates
Sand for use in roof screed shall comply with the requirements for sand for concrete as specified elsewhere herein.
3.2.3 Coarse Aggregates
Aggregates for use in roof screeds is to be 10mm and shall comply with the requirements for aggregate for concrete as specified elsewhere herein.
3.2.4 Water
Clean potable water, to conform to Concrete Works specification.
3.2.5 Roofing Membrane
The roof membrane shall be “Bituthene 8000 HC” manufactured by GRACE or equal and approved.
Proprietary high performance 1.5mm thick solar reflective roof cold applied, flexible pre-formed waterproofing membrane comprising a four layer cross laminated high density HDPE carrier film with a solar reflective surface and a self-adhesive rubber/bitumen compound which conforms to the following requirements:
Property Test Method Typical Value
Tape Strength ASTM D638 Long 5.2 N/mm
Trans 5.8 N/mm
Tensile Strength ASTM D638 Long 40 N/mm2
Trans 36 N/mm2
Trans 170%
Elongation Compound ASTM D638 125%
Tear Resistance ASTM D 1004 Long 270 N/mm
Trans 270 N/mm
Adhesion to Primed Concrete ASTM D 1004 1.8 N/mm
Adhesion to Self ASTM D 1000 1.8 N/mm
Puncture Resistance ASTM E 154 290N 65mm
Water Resistance ASTM D570
after 24 hrs after 35 days
0.14% 0.94% Environmental Resistance ASTN D543 Conform Moisture Vapour
Transmission Rate
ASTM E96 0.2 g/m2 / 24 hrs
3.2.6 Membrane related Products and Appurtenances
All products and appurtenances associated with the roofing membrane are to be proprietary items as supplied or recommended by the membrane manufacturer. Examples include solar reflective membranes and paint, surface primers, fillets, mastic sealants and flashings.
3.2.7 Insulation
600 x 1200 x 50mm thick proprietary extruded closed cell polystyrene rigid foam, with skin, and rebated edges.
The material shall have the following properties:
1. Five year aged average thermal conductivity of 0.032 W/mk when tested at 24oC in accordance with DIN 52612 or ASTM C-518.
2. Compressive strength of 280kPa average, when tested according to DIN 53421 or ASTM D-1621.
3. Water absorption of 1% in volume average when tested in accordance with ASTM D-2842.
4. Water vapour permeability of 0.6 perm inch average when tested in accordance with ASTM C-355.
A minimum density of 33 kg/m3.
3.2.8 Flashings
3.2.9 Separation Layer
Polyester based synthetic fibre mesh.
3.2.10 Gravel
15 to 30mm diameter smooth edged wadi gravel.
3.2.11 Paving Slabs
400 x 400 x 50mm thick proprietary white precast concrete paving slabs.
3.3 Execution
3.3.1 Preparation for Screeds
Concrete surfaces which are to receive screeds are to be thoroughly “scrabbled” preferably by mechanical means to form a regular rough texture. A tamped finish will not be accepted. Thoroughly clean the concrete surface and ensure that it is free from all loose particles and other extraneous matter which would adversely affect the adherence of the screed material.
Spray concrete surface with water to thoroughly wet the surface to be screeded. Allow free water to drain before screed application.
3.3.2 Lightweight Roof Screeds
Flat roofs shall be covered with a lightweight concrete roof screed which shall have a maximum density of 500 kg/m³ consisting of cement and sand with a foaming agent. Light weight aggregate may also be used. The work shall be carried out by a specialist agency approved by the Engineer strictly in accordance with the manufacturer’s recommendations.
The roof screed shall be laid to falls to ensure adequate run-off or rainwater and to prevent ‘ponding’. The minimum thickness shall be 50mm and the screed shall be laid in alternate bays of exceeding 3000mm in any direction.
The screed roof shall be thoroughly brushed clean of all dirt, loose stones etc. Any small cracks shall be filled with an approved tropical grade thixotropic cold bitumen emulsion with added rubber latex.
The screed surface to be waterproofed shall be even and smooth with any high spots knocked back and local depressions and sudden changes filled with epoxy mortar or similar high strength mortar to present a true surface. All sharp projections and arises caused by formwork etc. shall be ‘scrabbled back’ to give rounded corners. Primer shall be touch dry prior to the application of one layer of the membrane. The primer must not be poured onto the surface and care must be taken to avoid ponding in depressions.
All internal angle fillets shall be preformed triangular black PVC 50mm x 50mm extrusions with a wall thickness of 5mm, and shall be coated on two faces adjacent to the corner, protected by silicone coated release paper. The material shall be of a grade suitable for use in hot climates.
External corners shall be trowelled to provide a 25mm x 25mm splay. Where the membrane is to be terminated at an up stand, a 25 x 20mm deep splayed chase shall be provided. The chases shall be thoroughly clean and dry, and all dust, dirt, laitance etc removed from the faces by wire brushing and compressed airline.
All inside and outside angles shall be provided with an additional 300mm wide reinforcing strip of the membrane centred along the axis of the corner, prior to laying of the main membrane.
3.3.3 Roofing Membrane
Installation of roofing membrane shall be carried out in strict accordance with the manufacturer’s written instructions.
Ensure substrate is laid to the correct falls as shown on the drawings. Thoroughly clean the surface which is to receive roofing membrane. Ensure surface is dry and clear of loose particles and grease.
All roof up stands, parapets, service penetrations and expansion joints are to be constructed in accordance with the standard details as instructed on the
drawings, or as recommended by the membrane manufacturer.
Reinforce all inside and outside angles, and other vulnerable areas with an additional 300mm wide membrane strip prior to laying of the main membrane. Dress the roofing membrane into the roof rainwater outlets, which are to be of a design to allow draining both at membrane level and at the top of the roof tiles. Prior to covering the completed membrane request the Engineer to make an inspection. Clean and patch any damaged areas to the approval of the Engineer.
3.3.4 Roof Insulation Boards
Lay boards in accordance with the manufacturer’s instructions, in a brick bond pattern. Where the tiles are laid over a change or roof slope they shall be neatly cut with a saw along the line of the change in roof plane. The joint shall leave a small gap.
Cut the tiles carefully around up stands, pipe work and roof mounted plant. Alternatively in order to avoid small cut pieces the tiles may be set out to create a space round the up stand or pipe work which may then be filled with gravel or ballast.
3.3.5 Separation Layer
Lay a separation layer loose over the entire area to be insulated, carefully trimming and allowing a 50mm up stand at parapets, pipe penetrations, rainwater outlets, etc. Lap joints at least 300mm.
3.3.6 Gravel
3.3.7 Paving Slabs
Where indicated on the roof plans lay paving slabs with tight but open joints, secured in place with 1:6 cement: sand mortar dabs.
3.3.8 Pipes and Services through Roof Slabs
All waste stacks, ducts and pipes penetrating the roof slab are to be
weatherproofed in accordance with the Architects details, consisting of a block work up stand and concrete slab with the pipe turned through 90 degree. Plinths for equipment shall be built off the roof slab prior to commencing roof waterproofing. Plinths supporting pipe runs and cable trays may be built off the roof slab or precast plinths may be located on top of the insulation prior to laying paving slabs.
3.3.9 Testing
All horizontal roofing areas shall be water flood tested prior to the installation of the protection course.
No areas shall be water tested less than 72 hours after application of waterproofing membrane.
Water testing shall include flooding of the entire area either by section or in its entirety to a depth to be agreed with the Engineer for a minimum period of 72 hours.
3.4 Protection
The Contractor shall employ whatever methods are required to protect the roof at all times, up to the building handover, from damage from any cause
4
Carpentry and Joinery
4.1 General
4.1.1 Scope of Work
The scope of work includes the following: Manufacture and installation of:
• Doors and door frames • Counters and vanity units
• Fitted kitchen units (where required)
• Miscellaneous timberwork and specialist joinery All in accordance with drawings.
The doors should further comply with the specific sections of this specification.
4.1.2 Standards
Comply with the following standards where relevant and to the extent stated here.
• BS 5268 : 1991 Structural Use of Timber
• BS 1186 : 1988-91 “Timber for & Workmanship in Joinery” • BS EN 942 : 1996 Timber in Joinery - General Classification of
Timber Quality.
• BS 8000:1990, Part 5 Code of Practice for Carpentry, Joinery and General Fixings.
4.1.3 Setting out
All work is to be set out and constructed to the dimensions given and to the full intent of the drawings and specifications. Check dimensions on site before cutting or pre-fabricating components. In general, site dimensions will take precedence over drawings, the Engineer’s approval is however required in such cases.
4.1.4 Shop Drawings
Do not commence manufacture of joinery components without the prior approval of the Engineer and his agreement to the shop drawings. Details of construction shown on drawings prepared by the Engineer may only be altered with the prior agreement of the Engineer.
All work including joint types, fixings, etc must be detailed on shop drawings and approved by the Engineer before manufacture.
4.1.5 Samples
Prior to general manufacture, full size samples of each type of timber
construction must be fabricated and installed in order to approve all parts of the process.
4.1.6 Joinery in General
Unless otherwise specified, all joinery is to be purpose made, worked to detailed drawings where provided and constructed in accordance with approved best practice. It shall be mortised and tenoned, dowelled, dove-tailed, tongued, grooved, glued, pinned, screwed etc. as necessary and best suited for the particular purpose.
4.2 Materials
4.2.1 Timber Generally
All timber shall be sound, thoroughly seasoned, of mature growth, clean sawn, square-edged, free from sap, ring shakes, cracks, splits, large, loose or dead knots, boxed heart, wanly edges, insect attack, fungus growth, rot, dote or incipient decay, stained sapwood and other defects and shall be to the approval of the Engineer.
Timber shall be straight and true; any warped or twisted timers will be rejected. All materials and components are to be stacked on suitable bearers clear of the ground and protected from the weather until they are fixed in position. If necessary provision shall be made for temporarily covering or otherwise protecting materials and components after they have been fixed in position
4.2.2 Hardwood for Internal Use
Unless otherwise specified, selected Beech (Fagns Sylvatica) or Cherry complying with the requirements of BS EN 942,Class J2 without sapwood. Density to be approximately 700 kg/m3.
4.2.3 Hardwood for External use
Unless otherwise specified, selected Meranti Nimusu complying with the requirements of BS EN 942, Class J2 without Sapwood. Density to be approximately 700 kg/m3.
4.2.4 Exposed Timber
All faces of timber which will be exposed when the building is complete shall be wrought and shall have been selected as to quality of face. Grains shall be parallel to the length under max 60% degrees.
4.2.5 Pressure Impregnation
All Meranti timbers shall be vacuum treated for termite resistance and preservation.
Timber shall be impregnated by Hickson Vac-Vac process to achieve an average loading of 40 litres “Vascol WR” preservative per m3 of timber or equal.
All ‘cut ends’ joint forming, planning and/or any on-site cutting shall be liberally treated with Hickson “Vasele” end grain preservative.
4.2.6 Moisture Content of Timber
Timber shall be properly and carefully air seasoned to 20-25% moisture content prior to kiln drying. The moisture content shall be suitable for the situation of the finished timber but shall be limited to 11% ± 2% for internal use and 13% ± 2% for external work. When fixed in position the timber shall remain stable and free from any expansion or contraction or other movement which will detract from the satisfactory performance or required appearance of the
element. The timber shall be free from any drying defects whatsoever and there shall be no indication of shrinkage.
The Contractor shall replace at his own expense any timber which has been damaged or shrunk on finished work caused through the use of imperfectly seasoned timbers.
Immediately before manufacture the moisture content of timber should be ascertained using an electrical moisture meter to manufacturer’s
recommendations. Test 5% but not less than 10 lengths of each cross-section; average results shall be in the centre of the specified range.
During delivery, storage, fixing and thereafter to practical completion maintain conditions of temperature and humidity suitable for specified moisture
content(s) of timber components.
The moisture content at the time of matching to the dimension indicated shall conform to the requirements of the said standard specification for the kiln drying of timber, for items customarily kiln dried. The timber in any
consignment shall be deemed to be satisfactorily kiln dried if upon inspection of representative samples drawing from the consignment, tests indicate that for: Interior use/Interior joinery and door stock - At least 90% of the samples shall have a moisture content not exceeding 11% and the remaining samples shall have a moisture content not exceeding 13%.