This method offers a number of benefits, including longer spans and the ability to install more insulation, aiding the overall construction's thermal performance. However, the advantage which was of most interest to the client was the ease of installing plumbing and electrical services.

Richard Simmonds, Technical Director of T.Fleming Homes, explains: "During discussions with one of our clients, they raised the problem of running services through the floor joists. The obvious solution was to use Posi-Joists, however the second floor really needed an attic style truss.

“We simply asked roof truss designer Paul Honeyman at DTE Buckhaven if he could design us an attic truss using a Posi-Joist as its bottom chord, and we were delighted that Paul managed to get a design to work. Our client is very happy that we have provided them with a solution to the problem of running services through all floors in their build.”

The final roof structure comprised attic trusses with Posi-Joist bottom chords and raised tie trusses with cat-slide rafters. The DTE team produced all of the attic trusses for the project in under a day on the Buckhaven Birch table press.