Once an air barrier membrane and system components have been selected, it is important to determine how the materials will need to overlap and be sealed at the transition to the below-grade foundation to ensure continuity. Protection against air and moisture infiltration is only as good as the integrity of the connection. To be effective, the connection must be compatible, be able to accommodate varying shapes and ledges, have full adhesion to prevent water from travelling, and have the flexibility to deal with cracks, joints and thermal or minor structural movement.
The issues facing the construction industry have never been greater. Project timelines continue to get tighter. Specifications continue to call for greater product performance within ever-tighter budgets. Concerns over water penetration have now broadened to include energy efficiency and indoor air quality. Today, there is little, if any, tolerance for water infiltration due to design or field detailing errors.
Fluid-applied waterproofing systems provide seamless protection that allows no part of the wall to be left untreated or exposed to moisture penetration even in areas with complex detailing. These liquid systems eliminate the possibility of “fishmouths” or wrinkles, areas presenting the potential for water leakage and migration or movement behind any membrane that is not fully adhered. Localizing the source of leaks in these cases becomes extremely difficult and costly. In addition, the excellent flexibility, strength and adhesive characteristics of liquid systems allow them to bridge non-structural cracks, remain flexible at low temperatures and protect against water under hydrostatic pressure.
With today’s spray-applied waterproofing membranes, fully adhered, seamless protection is possible in one efficient pass. The efficiency of spray application allows at least four times more area to be waterproofed than with traditional application methods in the same amount of time. Systems are also currently available that are formulated for application to damp, or “green,” concrete, eliminating waits of two to four weeks for application. No priming or special surface preparation is required, so they may be applied to concrete as soon as the forms are removed and to masonry as soon as the mortar is dry. In some cases, protection courses may be applied the same day instead of having to specially prepare them for installation within the next couple of days.
This new efficiency is having a dramatic impact on contractor productivity, job scheduling and construction schedules. With the same teams, contractors can now take on more work and increase their profitability or limit the resources needed on jobs. Waiting periods, which complicate schedules and create problems for other trades, are eliminated. General contractors can streamline and expedite production schedules
Spray-Applied Waterproofing Connected to Fluid-Applied Air Barrier Put to the Test
The performance of Tremco’s TREMproof® 260 Spray-Applied Waterproofing Membrane as the below-grade system was tested with ExoAir® 230 Fluid-Applied, Vapor-Permeable, UV-Resistant Air Barrier Membrane at Tremco’s Sustainable Building Solutions Test Facilityto determine the comprehensive “connected” solution’s ability to ensure a tight building envelope.
When tested in accordance with ASTM E2357, no damage was witnessed during the duration of the testing and air leakage was at 0.0018 cfm/ft² at 75 Pa. When testing was conducted for ASTM E331, water leakage did not occur until 1050 Pa or a 94 mph wind load had been maintained for 1 minute and 9 seconds -- far beyond the standard test requirements at 300 Pa (6.24 psf). A Category 2 hurricane is reported as starting at 96 mph.
The sophistication of these products and their delivery systems is generating a new and highly efficient level of performance and productivity.