The scope of this procedure comprises the control of waterproof membranes installation and application on flat and inclined substrates.
The condition and moisture content of the substrate will be inspected and accepted by the subcontractor before commencement of waterproofing works on site.
A meeting will be held with specialist subcontractor to discuss the scope, sequence of work and inspection requirements.
Materials will be stored in accordance with the recommendations of the manufacturer especially volatile and limited life liquids.
All surfaces will be dry and free from dust and loose material by using the compressed air or vacuuming, prior to application of the roof water proofing membrane.
Any foreign matter such as oil, grease etc. or protrusions such as nails, concrete fins etc. will be removed to ensure a good bond and water tightness.
Primers, liquid membranes, bonded and unbonded sheets will be laid strictly in accordance with the manufacturer’s instructions, using laps, fillets and flashings as specified.
All the work areas will be subject to controlled access to ensure availability of roof and to prevent damage to the waterproofing membrane.
Following the installation of the water proofing membrane, suitable temporary protection board or permanent installation will be laid as required by the specification and good practice to provide protection against damage to the membrane while the other trades perform their operations.
The waterproofing subcontractor will submit a requisite guarantee for the waterproofing system against leaks. The guarantee shall be in the name of the Client and shall commence from the hand over date of the building.
A flood test will be applied, if specified. Repairs will be carried out until a waterproof condition is accepted.
The installed membrane will not be overlaid with permanent covering until it conforms to the specified requirements.
Inspections of installation and material will occur as per below Check Sheet for Roof Water Proofing.
- Condition of roof and moisture conditions accepted by subcontractor.
- Roof area cleared of loose material, projections and oil etc.
- Roof area isolated for membrane installation.
- Primer laid in accordance with instructions.
- Liquid membrane sheeting laid in accordance with manufacturer’s instructions (including bonding where specified).
- Spot checks on laps, fillets and flashings.
- Flood test carried out?
- Final inspection before boarding or screeding (including separation sheet)
- Check guarantee in place.