Controlling a structure’s air leakage, thermal performance and overall energy consumption arecritical to meeting the exacting performance standards of today's buildings. Tremco Commercial Sealants & Waterproofing is responding to this challenge by launching T3 Building Solutions, a high-performance sealing system for around windows and doors that controls thermal bridging and air infiltration which can lead to heat loss, occupant discomfort and premature structural deterioration.
With an innovative three-layer approach, T3 Building Solutions incorporates a vapor-permeable air barrier for the outer seal, a thermal layer for the middle and a vapor retarder for the inner seal. Working in unison, these three layers securely seal the connections or transitions from the wall-to-window assemblies which are critical to the air- and weather-tightness of the building. By creating an airtight and thermal bridge-free envelope, this unique application ensures that heat, and consequently the energy generated in a building, are not wasted.
T3 Building Solutions offers components appropriate for a broad range of applications. Since compression may be achieved in a stud wall construction, ExoAir® Trio, is an ideal 3-in-1 solution to seal out weather, thermally insulate and provide a vapor barrier to prevent unwanted moisture at the dry side of the wall assembly. ExoAir® Trio is a pre-compressed flexible polyurethane foam impregnated with synthetic resin that serves as a vapor retarder, preventing moisture migration into the building cavities. Within 30-45 minutes at 77°F (25°C), the foam tape expands to entirely fill the gap between the window frame and the wall with a thermally insulating and sound dampening layer. Finally, the exterior of the tape allows vapor diffusion while providing protection from the elements. With this three-level sealing of the wall assembly, moisture vapor will not be able to form condensation so the joint between the window and wall will stay dry.
For cavity wall applications, compression is not an option. In this type of application, T3 Building Solutions utilizes a three-component approach to ensure the window-to-wall joints are airtight, thermally efficient and vapor-permeable. The sequence begins with the application of ExoAir® Eco as the exterior seal. This pre-compressed flexible polyurethane foam tape expands to entirely fill the gap between the window frame and the wall within 20-45 minutes at 70˚F (25˚C) while its synthetic resin impregnation provides weather resistance against the most severe combinations of wind and rain. To provide thermal insulation in the cavity, ExoAir® LEF, a single-component, moisture-curing, gun-grade polyurethane foam, is applied to fill in the gaps around windows. Finally, ExoAir® Duo Membrane is used as the internal airtight seal to create a vapor drive to the exterior of the building. ExoAir® Duo Membrane is composed of a tear-proof woven fabric embedded into a polyethylene copolymer with a large expansion pleat for variable joint sizes and absorption of movement to create a unique window flashing membrane.
All T3 products have been rigorously tested at Tremco’s Sustainable Building Solutions Test Facility to meet requirements related to air leakage, thermal efficiency, sound dampening and vapor-permeability. Under ASTM E283, a window-to-wall assembly with ExoAir® Trio was tested to measure the air leakage rate. With a pressure differential of 75 Pa, which simulates a 25 mph wind, the air leakage value was 0.029 cfm/ft2 with an air exchange rate of 0.43/h @ 50 Pa, outperforming the passive house standard of 0.6 or less. Under ASTM E331, the same window-to-wall assembly was tested to ensure resistance to wind-driven rain. With the water exposure test set at 600 Pa pressure, instead of the standard 137 Pa, the assembly still passed with no water leaks. During sound dampening testing, the ExoAir® Trio assembly received a Sound Transmission Class (STC) rating of 54, outperforming typical home interior walls, which have an STC of about 33.
Under ASTM E283, a window-to-wall assembly with ExoAir® Eco, ExoAir® LEF and ExoAir® Duo was also tested to measure for the air leakage rate. With a pressure differential of 75 Pa, which simulates a 25 mph wind, the air leakage value was 0.005 cfm/ft2 with an air exchange rate of just 0.10/h @ 50 Pa, again outperforming the passive house standard of 0.6 or less. Under ASTM E331, this window-to-wall assembly was tested to ensure resistance to wind-driven rain. This time the water exposure test was set at 300 Pa pressure, instead of the standard 137 Pa for fifteen minutes, then increased to 600 Pa, 750 Pa, 1000 Pa, and finally up to 1500 Pa at five-minute intervals and the assembly still passed with no water leaks.
By simplifying the installation of window-to-wall transitions, Tremco T3 offers a proven, single-source solution that expedites production schedules, increases flexibility in project design, and seals in comfort and energy savings.