Detailed Method Statement shall be prepared as per individual contract requirements.
2. Relevant Process/Specification:
3. Tools/Equipment Required:
As specified by sub-contractor.
4. Procedure / Method:
Check and ensure that the surface of the concrete is free from loose concrete, oils, dust, stagnated water and other deleterious materials.
Foam concrete top surface level shall be calculated by considering the falls (1 % min or as specified) towards the drain point. Minimum thickness of foam concrete slab shall be considered as 50 mm or as specified.
Approval shall be obtained from the client prior to the preparation of level strips.
Level strips shall be prepared with cement sand mortar as per the levels shown / as specified to assist the layman to achieve proper slope on foam concrete.
The foam concrete shall be the well-proportioned mix of cement, (with or without) sand, water and foaming agent to achieve specified strength and density.
The approved mix shall be batched in the mixer machine and pumped to the roof for laying. Sufficient number of test cubes shall be made for testing strength and density.
This shall be cured for a period of 7 days or as specified.
All rough spots and bad surfaces shall be made good before laying the membrane.
Comer fillets / Angle fillets shall be made with cement-sand mortar near to parapets and up stands which assist to turn the membrane smoothly from Horizontal to Vertical direction.
Leave the surface to dry for a period of 24 hours and apply approved primer, which is suitable for the membrane.
Apply adhesive and lay spot bonded membrane / tiles on top of the prime red surface.
Follow manufacturer’s recommendation for overlap of membrane on both directions.
Skirting membranes shall be laid over the corner fillet and on Vertical surfaces and shall be terminated in the groove, which has been made for this purpose.
This groove shall be filled with sealant.
Water leakage testing shall be done after successful completion of lying of membrane.
All the drain points shall be plugged watertight and pool 75 mm deep water over this surface for a period of 72 hours. Visible leakage shall be checked on soffit of slab. The leakage, if any, shall be rectified and retested as required to achieve leak proof slab.
50 mm thick insulation board, filter membrane, and gravel topping shall be laid one above other, (or as specified).