White Cap has the capability to supply the full system for all your waterproofing projects, as well as all the items on your material list, including sealants, adhesives, joint tapes, mastics, and waterstops. These high-quality products are paired with expert advice that can support not only your design phase, but also the timely delivery of products to your jobsite.
Let’s look at some of the types of waterproofing systems often specified on commercial projects.
Cold Fluid-Applied Membranes
Cold fluid-applied membranes provide a waterproof barrier on both horizontal and vertical applications and can be applied post-placement, both above and below grade.
Compared to sheet membranes, these solutions are typically faster to install because there are no sheets to cut. Installers can coat the entire surface with a continuous membrane that leaves no open seams at joints and can also use common tools such as sprayers, rollers, squeegees, and/or trowels to apply.
As the structure settles or moves, the fluid-applied membrane moves with its host substrate. These membranes are well suited for projects that have irregular shapes and surface textures.
Sheet membranes are factory-produced sheets that meet thickness standards. The thickness is determined based off the resistance required for the anticipated hydraulic pressure. Manufacturers offer these sheets in a wide array of materials including bentonite clay, modified bitumen, rubber, polyethylene, polypropylene, ethylene propylene diene monomer (EPDM) and reinforced polymers.
Pre-placement membranes are placed on the inside of the concrete form. As the concrete hardens, the membrane fuses to the concrete element with a chemical reaction.
Post-placement membranes often have adhesives on one side that securely affix the membrane to the concrete, known as self-adhering or ‘peel and stick membranes.’ Alternatively, contractors secure non-adhesive sheets using straps, anchors, and fasteners.
Hot Rubber Membranes
Hot rubberized membranes are fluid-applied waterproofing systems used to create monolithic membranes on large surface areas. Contractors have found the continuous elastomeric membranes to be an efficient material to waterproof bridges, parking structures, promenade decks and tunnels after they are constructed. Hot rubberized materials consist of a blend of asphalt and modified rubber polymers containing mineral stabilizers. The formulations provide an excellent combination of toughness and low temperature flexibility. The fully cured membrane features a very low absorption and vapor permeance. These products also conform well to surface irregularities.
Cementitious membranes are fabric-like materials made with a Portland cement-based coating combined with a waterproofing agent. You apply them to prevent water, water vapor, and moisture from penetrating concrete surfaces. The membranes are flexible so you can easily bend and position them on curved exteriors. These materials are commonly used on structures that contain water such as storage tanks, swimming pools, and pumping stations.
CrystallineCrystalline waterproofing products are topically applied solutions that contain special chemicals that will react with the cement in the concrete. After application, when the solution is very thin, it transports the chemical into any open spaces beneath the surface. Once inside the voids, the chemicals combine with the cement particles already in the concrete.
The reaction causes the insoluble crystalline structure to fill pores, cracks, and capillaries. The treated concrete itself becomes a membrane by effectively reducing concrete permeability and sealing hairline cracks. The denser, hardened structure also obstructs water from seeping past the treated zone.
DampproofingUnlike waterproofing that keeps out both moisture and liquid water, dampproofing is specifically intended to keep out soil moisture. The International Residential Code specifies that "foundation walls that retain earth and enclose interior spaces and floors below grade shall be dampproofed from the top of the footing to the finished grade.” These products, which typically include bituminous coating and acrylic-modified cements, are used when the residential foundation is placed in an area with a high water table, or if there are concerns about soil water conditions.
Unlike other treatments, dampproofing is not a membrane but a coating that is either sprayed on, or hand applied to the outside of the wall. For maximum effectiveness, dampproofing must be a part of a construction detail that includes proper drainage at the residential footing.