U.S. Window Makers Look at Passive House Standards

March 19, 2012

Rovereto, Italy—More European window makers are moving to triple glazing to meet new “passive house” standards in Germany, Switzerland and Italy, according to Cristian Zuani, export manager of Zuani S.r.l. The strict whole house standards, designed to significantly reduce energy consumption, are being driven by government incentives and are enjoying increasing popularity among architects.


Cristian Zuani reviewing the development of "passive house" standards in Europe.

The passive house movement presents an opportunity for high-end window makers, Zuani said, speaking to a small group of U.S. custom wood window producers. The group, organized by Rangate Inc., a U.S.-based importer of woodworking tooling, and supported by Functional Fenestration Inc., a supplier of tilt/turn and other European hardware systems, was also heading to this week’s Fensterbau in Nuremberg, Germany.

The new standards allow some trade-offs in individual homes, but establish criteria that translate into demand for a window with a European U-factor of at least 1.5 ranging down to 0.8 (about 0.26 down to 0.14 U-factor in U.S.), Zuani stated. In the wood window business, the standards are not only driving a shift to triple glazing, but also warm-edge spacers and changes in wood frame designs, such as the use of hollows and cork.

The three programs driving these demands are the Passivhaus Institut standard in Germany, the Minergie program in Switzerland and Italy’s KlimaHouse. One reason window manufacturers are studying these programs, Zuani noted, is that the trend towards green remains very strong in Europe. Given general economic conditions, “it’s been the one market segment to grow,” he added.

U.S. window makers touring the tooling manufacturing operation. 

Zuani also welcomed the window manufacturer group for a tour of the company’s facility. The company provides wood tooling, as well as design assistance and a variety of other support services to hundreds of wood window producers in Europe.  One of the highlights of the tour was the introduction of a new ultra-thin diamond coating under development that is expected to greatly extend the life of cutting tools.  

Attendees on the tour are beginning discussions, supported by Zuani, Rangate and Functional Fenestration, to develop a common tilt/turn program that would enable their small custom shops to meet testing and certification requirements for energy and structural performance more cost effectively.