Timber joist structure

And here's the plan for the internal timber structure. Loving the sketchup program now, not bad for free...

Whilst building this, the outside panels will also need to go up. To save on weight (and money), the outside panel will be from basic hardboard. It's only 3mm but should be able to keep the rockwool in place which will be inbetween the timber joists. Construction starts this week!