Detailed programming of all MEP work activities will be prepared in full coordination with the main contractors programme. Builder’s works drawings will be prepared to show all openings sleeves and cast in items, Wherever necessary back up calculations will be prepared and submitted to Consultant. For specialist equipment a suitably qualified specialist subcontractor will be used.
Working Shop Drawings
Working drawings will be prepared for relevant items and equipment. They will be coordinated with other services and works. Working drawings will be prepared in accordance with the requirements of the contract and the statutory regulations by the local service authorities for electricity, water, drainage, telephone and civil defense. The working shop drawings will be submitted to the consultant for approval and also to the local authorities or service authorities where applicable. Relevant authorities will be kept informed about the methods of construction and their approval shall be obtained as necessary. Working drawings will be prepared well ahead of the related construction work to allow enough time for review and comment by the consultant, or service authority.
Material Submission & Approval
Materials of construction to be incorporated in the works will be submitted for approval in proper format approved by the consultant. Priority will be given to approval of materials. that are required for enabling works as well as chillers and transformers. Special attention will be given to storage of material during the course of the contact Covered areas will be used for products. Which need protection from sunlight and weather conditions. Dedicated construction teams with adequate supervisors will be allocated to the various designated areas based on CPM and available areas.
AIR CONDITIONING CONSTRUCTION STRATEGY
DUCT FABRICATION
Ductwork work will be fabricated using a computerized design and fully equipped sheet metal manufacturing plant. The following procedure will be used for the fabrication of the ductwork.
- Drawing review by fabricator
- Prepare print out showing types of pieces, number of pieces, area and weights
- Separate standard straight pieces
- Run AutoCAD optimization programme for best utilization for fitting shape.
- Data transferred to operator for cutting machine
- Marketing and cutting pieces for ducts.
- Lock forming and auto flanging
- Folding assembly of pieces to duct.
- Dimensional shape, quality and inspection
- Labeling of items delivery to site.
Ductwork will be delivered from the fabrication area when required in a coordinated manner as follow:
- Mark out support locations at duct work based on working drawings.
- Drill holes in concrete element. fix anchors arid drop rods.
- Connect duct pieces in appropriate lengths arid widths between support rods.
- Lift and raise ducts from floor to support level manually for small sections or mechanically for larger sections.
- Fix angle supports and nuts to support dust at correct level.
- Correct more pieces in appropriate lengths and install at desired level
- Connect adjacent duct sections by slip joints or angle flanges as specified with sealant or gasket as appropriate.
- Fix necessary accessories such as VCD’S. FDS. VAV’S access doors, veins and fans
- Carry out pressure test to check for leakage monitor with suitable instrument,
- After approval of coordinated reflected full ceiling drawings commence installation of flexible ducts and air terminal devices.
DUCTWORK INSULATION
After ducts have been satisfactorily tested for leakage, insulation work will be carried out.
- Clean the external surface of the duct to remove grease, moisture or deleterious material.
- Apply specified adhesive In surface of ducts at the manufacturers recommended application rate.
- Fix self-adhesive stickpins on spot welded pins at the specified intervals
- Cut and prepare insulation board pieces in required sizes according to manufacturer’s recommendations to prevent compression of insulation to less than 75% of its nominal thickness. Fix the same on the duct surface with the help of stickpins and previously applied adhesive, ensuring that the edges are straight and closely butted
- Fix the retaining speed washer on the stickpins / spotter pins.
- Seal the joints and seams with vapour barrier mastic whore required as per the specifications
- Seal the joints of insulation by aluminium foil adhesive tapes
- Apply the first coat of vapour barrier wrap with canvass/glass cloth and then apply second coat of vapour barrier.
- Apply Insulation continuously through walls and partitions except fire rated walls and partitions
- For fire rated will and partition penetrations, terminate insulation at fire damper sleeves.
ALUMINIUM CLADDING OF INSULATED DUCT AND PIPES.
Cut the aluminium sheets of specified thickness to make boxes of the required size. Between the surfaces of the canvas cloth, wrap on top of the insulation with brush. Fit boxes of aluminum over insulated ducts and pipes. Rivet on longitudinal and transverse blots and further if required with waterproof sealants.
CHILLER WATER PIPE INSULATION
Ensure pipes of correct specified type with appropriate documentation and certification.
- Remove end caps clean and paint with red oxide.
- Drill holes in concrete slab and fix anchors and drop rods and per approved working drawings.
- Fix pipe hangers and install pipes
- Pipe connections may be either welded or flanged and belted dependent on the specification.
- For welded pipes approved welder will be used.
- Fix valves in pipes.
- Carry out pressure testing of the pipe.
- After successful pressure testing carry out insulation / cladding work.
- Prior to testing and balancing of chilled water system treat pipe with recommended chemicals and flush with water.
PLUMBING
During the foundation and concreting stage of the civil works, suitable approved sleeves will be provided in the beams, slabs and columns. The underground drainage work will be carried out simultaneously with the progress of the civil works. Proper slopes will be maintained and the pipeline will be checked for water tightness by subjecting the pipes to required pressure as given in the contract documents. All the drainage pipe work in the horizontal run will be supported.
- Adequate traps will be provided with water seal. Pipeline passing through fire barriers will have fire-stopping sleeves. Standard method of construction as specified In contract documents will be followed, Special care will be taken for safely aspect during execution.
- During installation and handing pipe and things will be closed by arid caps to avoid the ingress of dust and dirt.
- Plastic pipes will be stored in a covered area to avoid deterioration due to exposure to UV sunlight.
- Installation levels will be taken as those defined in the drawings and specifications of the construction contract.
- A check will be made with the municipality or statutory authority for their relevant level system arid benchmark to ensure coordination with the discharge drainage.
- Buried pipe work will be carried not in coordination with the external civil works.
8. A review of all the contract drawings will be made to ensure proper slopes are specified. - External installation connections to municipal drainage department will be offered tor inspection by the relevant authority.
- Adequate clean out and traps will be provided unless specified elsewhere in the contract.
- Copper pipes will be joined by the silver brazing method arid tasting of joints will be carried out In accordance with the contract.
- Prior to delivery and installation of sanitary ware a trial mock up installation will be prepared and offered for review and approval by the consultant.
- All fire fighting installation will be submitted far approval by the civil defense department and water supplied pipe will be flushed and disinfected in accordance with the contract requirements.
ELECTRICAL WORKS METHODOLOGY
The programme for the sequence and coordination electrical and construction work activity will be based on the main activities shown below
Electrical Activities
- Lay underground ducts or sleeves.
- Place sleeves I box outs in concrete slabs.
- Fur conducting DB and outlet boxes in wall recesses,
- Surface conduit.
- Fix shade or cable trunking
- Fix surface DBS and SMDB’s
- Install wiring, cabling & power cabling.
- Install suspended ceiling.
- Fit surface lighting fixtures.
- Fix UPS
- Fix fire alarm devices and wiring accessories
- Fix recess light fixtures.
- Fix lighting control system.
- Install bus bars.
- Install MDB’s
- Install OG sets & associated works.
- Install transforms and HT cabling.
- Install earth pits.
- Testing
The installation of electrical equipment can be briefly summarized as under to be followed by electrical engineering team:
- Underground sleeves for electrical services will be commenced during the earthwork and ground preparations.
- Concealed conduits, sleeves/ducts etc. in the slabs and walls will be installed during the slab concreting and wall construction i.e. block work.
- Cable support systems which includes the cable trays, trunking etc. installation will commence after the slabs are ready and in coordination with the other services i.e. mechanical, Plumbing and Fire Fighting.
- DB’s SMDBs and MDBs installation will commence after the designated walls and electrical rooms are complete in almost air respect of dell activities.
- Circuit wiring and cabling work is carried out after the completion of structural and block work including the plastering.
- Installation of lighting fixtures, FA system and ELV equipment will be after completion of the painting activity.
- External works including earthing lightning protection and external lightning will commence with the preparation of land fertile landscaping and roadwork.
- All the above works are to be inspected by the concerned authorities immediately after completion of each activity to ensure that all the specifications are complied during the installation and the installation is carried out as per the manufacturers guidelines.
- Testing will be carried out progressively after each activity. Final testing will be carried out prior to handover.
- Initially the project consultant will carry out inspection testing and this will be followed by Inspection by the local power authority.
- Incoming power supply by the local power authority (the service connection) will be given when the latter completes the associated works.
COMMISSIONING STRATEGY
- Detailed method statement will be prepared specifically identifying sequence of testing and commissioning at least 60 days prior commencement of testing works.
- During that stage detail schedule of activities regarding testing and commissioning will be prepared.
- Contractor will wherever specifically required appoint independent testing agency, which specializes in the balancing, testing and commissioning of ventilating and air conditioning.
- All instruments used by that agency will be accurately calibrated and maintained in good working order.
- All rest certificates for instruments will be issued before approval of commencement of testing works.
- All testing procedures will comply with the specification and relevant commission codes.
- Testing agency will provide guarantee according to the specification.