This article is only available to GBA Prime Members Start Free Trial Already a member? Log in In most climate zones, achieving the Passivhaus standard requires more expensive windows, higher insulation levels, and greater attention to air-sealing details than less stringent construction practices. It should come as no surprise that homes with these features cost more to build than homes complying with easier-to-meet standards.While fans of the Passivhaus approach usually concede these facts, they note that the added costs yield many benefits, including lower energy costs, better indoor air quality, and improved occupant comfort — and that these benefits justify the higher construction costs. A research study in Austria looked into this issue, and came to a surprising conclusion: occupants of non-Passivhaus apartments were just as comfortable as occupants of Passivhaus apartments. Moreover, when researchers compared the energy needed for space heating, both types of housing used about the same amount of energy. A multi-family project in Bregenz The research was conducted at a multifamily housing development in Bregenz, Austria, called Wohnpark Sandgrubenweg. The city of Bregenz is located in the Vorarlberg region of northwest Austria.The project consists of 76 apartments in four buildings, each four stories tall. The apartments range in size from 592 square feet to 1,076 square feet. The apartments are owned, not rented, by the occupants.Construction of the development began in 2005. The developers based the buildings’ design on green principles. For example, the underground parking garage includes a “bicycle service station” designed for do-it-yourself repair jobs. The garage also includes a “car-sharing stand.” (Further details on the car-sharing facility are not available.)Space heating and domestic hot water are provided by a central boiler fueled by wood pellets. A hydronic distribution system circulates hot water through in-floor tubing. Apartment owners pay for electricity and space heating based on meters that measure energy use in each apartment. Some of the… Sign up for a free trial and get instant access to this article as well as GBA’s complete library of premium articles and construction details.