Threshold support system gains KIWA certification for passive house builds

This article was originally published in issue 52 of Passive House Plus magazine. Want immediate access to all back issues and exclusive extra content? Click here to subscribe for as little as €15, or click here to receive the next issue free of charge

The Isoquick system is prefabricated to suit specific cill details and slots into pre-cut rebates in the perimeter insulation, allowing rapid installation on site. It is rated to support loads of up to 380 kg per linear metre, making it suitable for large door sets.

"Placing the frame cill above the insulation is the most thermally advantageous position, but until now supporting it properly has been tricky," said Jonathon Barnett, general manager at Build Homes Better.

"The Isoquick threshold support system is designed to support even the heaviest door sets,” he said.

The system was used on a recent passive house project at the Wintles in Shropshire, built by PYC Construction. "It's a really neat detail which saves so much time and headache on site," said Ben Meade of PYC. "The edge insulation is rebated before it arrives, the supports come complete with Compacfoam to the sizes required, and they just drop into place. No fiddling around cutting and fixing back to the slab."

Threshold detailing is frequently overlooked during early construction stages yet resolving it retrospectively can be complex and costly. "Isoquick's thermally broken bracket system provides the flexibility and assurance needed to position even the heaviest door sets in the optimal thermal location without compromising structural performance," said Luke Gilman, windows department manager at 21 Degrees.