1. MEASURE THE SQUARES
Once the beam sealant had dried, we measured the sizes of all the squares we had to fill with insulation.
Safe to say they were not all exact squares/rectangles, I mean, they looked square, but the beams were not always at exact right angles to one another, which proved to be a slight problem later.
We also used our layout planner a lot here to get the exact measurements of the floor instead of going back and forth remeasuring everything.
2. SQUEAKY SQUEAKY
We used a 25mm PIR insulation board, as it is rigid, has good thermal properties, and is easy to work with.
And then we tried to cut it up with a bread knife and crafting knife.
We much preferred the crafting knife since it didn’t produce PIR crumbs everywhere, although it did squeak a lot more, so Sam had to run out the room… foam squeaking is his ‘nails on the blackboard’. 😖
3. THE TEST FIT THAT NEARLY FIT…
Once cut, we test to fit all our pieces, and none of them quite fit in their holes (blame Sam’s measuring).
Okay, it wasn’t actually Sam’s measuring skills; it was the incompatibility of a Sharpie marker line with a crafting knife cutting blade. The sharpie marks were a 2-3mm thick line, and the crafting knife blade only cuts a 1mm thick line, if that.
So, as the boards were cut, the cuts were made both on the inside and the outside of the line with no thought about the error.
Hence everything was a few mm out, and then when you add on the fact our squares weren’t entirely square…yeah.
After spending a few hours trimming them down, they all fit in their respective holes. 🛠️
4. MAKE THE BLUE BEAMS SHINY
Having made the insulation fit, we taped over the blue beams with 100mm aluminium foil tape. This is to ensure an airtight seal for the whole top surface area of the floor, allowing for a good moisture barrier and a continuous radiant barrier.
100mm was wide enough to cover and overlap the beam with the adjoining insulation boards. We also covered parts in the PIR board that weren’t foil covered with this tape.