Passive Windows, part of the Soundcraft joinery company, has catered for the increasing demand for thermally efficient buildings and British tastes in window design by launching what it believes to be the first outward opening timber passive windows.
The open-out windows received their first public airing at the exhibition running alongside TRADA’s In touch with timber conference, which the company co-sponsored.
Manufactured at the company’s Chelsfield, Kent factory, the windows provide U-values of 0.8W/m²K for the glass and frame combined (not just the centre pane), with solar heat gains of over 50%. These figures match Passivhaus requirements and can help meet the upper levels of the Code for Sustainable Homes.
“So far all the [other] passive windows in the UK are imported and inward opening,” said Terry Marshall, managing director of Passive Windows. “So we decided we’d offer an alternative.” Outward opening windows were not intrinsically better than inward opening, he added, but were by far the preferred option in the UK.
Around £250,000 was invested in new manufacturing technology, including a Stegherr counter profiling machine, a Hoffman mitring machine and a Weinig optimising saw, all of which were purpose built for the company.
“The mechanics of the outward opening windows are different, meaning the sections are larger and heavier,” said Mr Marshall. “They are also triple-glazed, so we’ve also had to invest in appropriate ironmongery.”