Historical: Foundation Waterproofing Sheet Membrane - 2015
This information reflects our best understanding of product composition in 2015.
Below grade waterproofing products range from cementitious waterproofing to liquid applied membranes to sheet membranes. The main advantage of sheet membranes is their consistent thickness. These membranes also have good elongation and flexibility...
More about Historical: Foundation Waterproofing Sheet Membrane - 2015
Below grade waterproofing products range from cementitious waterproofing to liquid applied membranes to sheet membranes. The main advantage of sheet membranes is their consistent thickness. These membranes also have good elongation and flexibility to move with the building. The most common sheet membranes are self-adhering rubberized asphalt membranes. These products are often used to waterproof foundations and other below grade structures. They are comprised of a rubberized asphalt adhesive which is laminated to a polyethylene film, with a release liner applied to the adhesive side. The membrane comes in roll form and can be applied horizontally or vertically. A primer is required on concrete prior to application of the membrane. Once the membrane is applied, it must be rolled with a hand roller to ensure a complete bond to the substrate. Some products have a selvage edge of asphalt adhesive to aid in sealing between sheets, but in order to ensure continuity, sheets must be overlapped by a minimum of 2-3 inches and the seams rolled to ensure adhesion. Some products may require additional sealing at corners or edges or additional protection from damage. Care must be taken not to damage the membrane during backfill.
A more up to date Common Product is available here: https://pharos.habitablefuture.org/common-products/2078982.