Week 14, Day 1:

• Site meeting #3 with the Architects.
• The start of work finishing off the top of the masonry cavity walls ready to receive the sole plates of the SIP construction that will form the second floor and roof.

Week 14, Day 1

The design of the solution for closing off the top of the masonry cavity walls has been the subject of much discussion over the past week. The challenge has been to balance the structural and thermal efficiency aspects. The chosen design consists of a “ladder frame” structure with (relatively) little timber spanning the cavity. The frame will be insulated and will then get a layer of plywood on top in order to seal the cavity. The SIPS panels will sit on the plywood.

The frame is deliberately set back 50 mm from the outside edge of the blockwork. There will be a 50mm layer of insulation over the outside of the SIPS panel and the timber frame, helping to reduce the thermal bridge.

Ladder frame structure on top of cavity walls

Note the green and white plastic packers used to ensure the frame is level.