In Portland, Oregon, urban expansion is controlled by setting urban growth boundaries to promote the efficient use of land and to protect farms and forests from urban sprawl. This forces creative use of land. In the case of The Cambridge, an odd-shaped, almost unbuildable lot in a prime location with zoning regulations specifying that buildings can’t be more than 100 feet across, has been transformed with exclusive penthouses, condominiums and town-houses. Each offers an unobstructed view of mountains and the city and private settings within walking distance of shopping, dining, entertainment and work. Steep grades between buildings with landscaped and paved areas and slab over occupied spaces created difficult conditions, requiring solutions to a variety of construction challenges and particular attention to transition details.
Particularly when jobs are as complex as The Cambridge and include a variety of different substrates, levels, grades and connections, the scrutiny by consultants is intense because nothing is minor when it comes to waterproofing. It cannot fail. Having a local technical field sales representative on-site to help guide in the selection of products right for the application, to make sure products are used correctly especially in critical areas and to do pull tests helps instill general contractor confidence in the quality of the job. Having many of the products supplied by one company also increases the efficiency and lessens the risk associated with complex jobs.
With so many different conditions on the job, many different waterproofing products were required. Storefront silicone-based systems needed to be compatible with polyurethane systems. Substrates included metal panels, brick, concrete and even sheetrock. To ensure a weatherproof system, a secondary seal with the ExoAir® Self-Adhered Membrane was used around the window system. With five stories on top of a two-story garage and balconies, walkways and landscaped areas on a sloped lot, details were critical. The ultimate in waterproofing was required, but weight was an issue over occupied areas. Using Vulkem® 360NF, sloped areas could be built up. With each transition or problem area presented, though, a tested solution could be provided – from below-grade throughout the project.
Vertical Back-Filled Wall Conditions
Paraseal® HDPE/Bentonite Sheet Membrane Dual Waterproofing System.
TREMDrain® 1000 and TREMDrain 1000T, two-part prefabricated drainage material and protection boards.
Horizontal elevated slabs over occupied space
TREMproof® 150 Hot Rubberized Asphalt, a one-part, 100% solids, hot-applied, rubberized asphalt waterproofing membrane.
TREMproof 250GC Waterproofing Membrane, a revolutionary high solids, one-part, cold fluid-applied elastomeric waterproofing membrane that can be applied to green or damp concrete in a single lift up to 120 mils.
Balconies and Walkways
Vulkem 360NF Polyurethane Basecoat, a water-cured basecoat that can be mixed with aggregate for a leveling compound to fill deeper, pitted areas or level back-sloped areas.
Vulkem 350/351 Pedestrian Coating System, an attractive composite waterproofing system comprised of tough-curing liquid polyurethane.
Glazing Applications, Window Perimeter and All Vertical Control Joints
Spectrem® 1 Silicone Joint Sealant, an ultra-low modulus, high-performance, one-part, moisture-curing sealant ideal for use on the most demanding, dynamically moving joints.
Spectrem® 2 Structural Silicone Sealant, a medium-modulus, one-part, high-performance, neutral-cure silicone sealant-ideal for a variety of perimeter caulking and glazing applications.
Secondary Seal Around Punched Windows
ExoAir® 110 Self-Adhered Air & Vapor Barrier Membrane, to prevent air infiltration/exfiltration, vapor transmission and water penetration.