Product Guide HVAC Accessories Researchers have shown that fabric ducts, like this red DuctSox installation, distribute air 24.5% more efficiently than metal ductwork. Photo: DuctSox Behind the recommendations Related articles Behind the recommendations Related articles HVAC Accessories The best-in-class fans, pumps, ducts, dampers, and other HVAC accessories and supplemental equipment More about HVAC Accessories Textile Ducting from KE Fibertec Three Sources of Air-Pressure Problems in Buildings Air movement in and through buildings caused by pressure differentials has important effects on performance and safety. Underfloor Air: Rising Above a Checkered Past EnGuard GlassFree Polyester Insulation While EnGuard building insulation is new, Vita Nonwovens is not. Breaking the Bonds of Bad Sealant Jobs Seals at window openings and other penetrations need to be done right the first time. Are your seals failing because of the most common application error—forgetting the bond break? The Hidden Science of High-Performance Building Assemblies Any four walls and a roof make an enclosure, but for efficiency, comfort, and durability, those elements have to be meticulously designed and installed. Putting the Duct Back in Ductless Mini-Splits Natural Ventilation: The Nine Biggest Obstacles and How Project Teams Are Beating Them Designers are reinventing the art and science of passive comfort control even where climate and culture favor mechanical systems. 10 Green Building Products They Still Make in the U.S.