Manchester house achieves top class airtightness with Kingspan TEK

This article was originally published in issue 19 of Passive House Plus magazine. Want immediate access to all back issues and exclusive extra content? Click here to subscribe for as little as €10, or click here to receive the next issue free of charge

Clients Steve and Mel Howarth hired PHI Architects to create their dream home, and after considerable research, PHI selected the Kingspan TEK building system for the walls and roof of the structure. The firm worked closely with highly experienced Kingspan TEK delivery partners, Point1 Building Systems, to achieve the energy efficient design.

Architect Sara Darwin commented: “Steve and Mel specified a structural insulated panel construction in their initial brief as they were keen to utilise the benefits of off-site fabrication. The Kingspan TEK building system scored highly on thermal efficiency as the core insulation material has a lower thermal conductivity than other products. As such, wall thicknesses could be minimised which was critical given the relatively tight plot.”

“Minimising air leakage was also essential as it allowed us to incorporate design elements, such as an L-shaped living space, which added extra external surface area. Point1 Building Systems were responsible for achieving the interface detailing I designed.

They were very confident that we would meet the air leakage requirement as the jointing system and OSB3 facing of the TEK panels inherently support airtight constructions. With the added membranes and tapes they installed, we were able to achieve an outstanding test result of 0.45 air changes per hour at 50 pa.”

Kingspan TEK building system panels comprise an OSB3 facing either side of a highly insulated core and can deliver U-values of 0.16 W/m2K or better. Point1 Building Systems worked alongside Kingspan Insulation’s technical services to develop a detailed specification which was virtually thermal bridge free.

The panels are factory cut to each project’s unique specification, which supports a fasttrack erection programme and provides significant design freedom. “The Kingspan TEK building system allowed us to design the first-floor rooms with open ‘vaulted’ ceilings,” Sara Darwin explained. “The tall ceilings create a feeling of space and light and the overall daylight qualities in the house are excellent.”