If Homelink is designed for the way people really want to live, the lower level is where they will want to spend much of their time. With its dedicated home theater, efficiency kitchen, billiard room, and huge bonus spaces, this level hits multiple hot buttons with today's buyers. And, unlike a basement that's built out later on, this one was designed from the beginning to stay dry and livable.
To help prevent mold formation, BSC came up with some specific requirements. These began with a below-grade exterior of poured concrete. That was covered with Koch Waterproofing's Tuff-N-Dri, a two-part system in which a flexible membrane is sprayed on then covered by a tough foundation board.
The at-grade, walk-out basement includes a billiard room and small kitchen, plus two large storage pantries. The kitchenette has warm cabinetry balanced by a stainless steel sink, microwave, ice maker, metallic backsplash tiles from Crossville Ceramics, and pendant lighting from Restoration Hardware. Wood wainscoting lines the walls, broken up by cultured stone columns in Owens Corning's Bucks County pattern.
Next, insulation was applied to the inside of the concrete basement walls. "We needed to use a material that was non-moisture sensitive--but would breathe," Lstiburek says. "So we recommended 'unskinned' extruded polystyrene. The material breathes only because it's less than an inch thick." That ability to breathe allows wet areas to dry out before mold can form.
Next, mechanicals were chosen that would further reduce the mold and moisture risk. In the fully conditioned lower level, a mechanical room contains the ber-efficient Carrier HVAC setup, which includes a zoning system, humidifier, gas furnace, electronic air cleaner, and energy recovery ventilator (ERV). "A normal A/C system doesn't have enough moisture removal in the summer and doesn't add moisture in the winter," Lstiburek notes. "This system addresses both of those concerns--and improves indoor air quality with [ERV] dilution."