What is Sheet membranes waterproofing? Explain in details with application procedure and typical use.

Sheet membranes are pre-manufactured, flexible sheets of waterproofing material that are used to create a barrier against water intrusion. They are commonly used in construction to waterproof roofs, foundations, and other structures.

The application procedure for sheet membranes typically involves the following steps:

1. Surface preparation: The surface to be waterproofed must be clean, dry, and free of any contaminants that could affect the adhesion of the membrane.
2. Priming: A primer is applied to the surface to improve adhesion and ensure a strong bond between the surface and the membrane.
3. Installation: The sheet membrane is cut to the required size and shape and then placed over the surface. The edges of the sheet are sealed using a waterproofing sealant or adhesive to create a continuous barrier.
4. Overlap and reinforcement: The sheet membrane is overlapped at the seams and reinforced using tapes, flashings, or other materials to ensure a watertight seal.
5. Curing: After installation, the membrane must be allowed to cure and dry completely. The curing time will depend on the specific product and the conditions, but it typically takes several hours to a few days.

Typical uses of sheet membranes include:

1. Roof waterproofing: Sheet membranes can be used to waterproof flat or low-slope roofs, as well as to create waterproof decks and balconies.
2. Foundation waterproofing: Sheet membranes can be used to waterproof basement walls and foundations to prevent water intrusion.
3. Below-grade waterproofing: Sheet membranes can be used to waterproof below-grade structures such as underground parking garages and retaining walls.
4. Waterproofing of wet areas: Sheet membranes can be used to waterproof areas such as showers, bathrooms, and swimming pools.

Sheet membranes offer a number of benefits, including ease of installation, durability, and the ability to create a continuous, watertight barrier. However, care must be taken during installation to ensure that the seams are properly sealed and reinforced, to prevent water intrusion.