Our roof exists out of two frames. A big frame for the back and a smaller frame for the front. Both are made with 240x38mm SLS beams. We first screwed the outer beams of the big frame together so we could still lift it up onto the roof before it became too heavy. Next we added the spacer beams inside this structure with a distance of 60 cm (so it matches the width of our sheep wool insulation). We added some extra beams on specific places where our bed system will be attached to the roof.
Next we started covering the inside of the roof frame with 12mm ESB panels. We made sure to leave some space (4-5mm) between the roof and wall panels so they still have some room to expand when the wood is taking up more moisture. We filled up all the screw holes and seams between the boards with putty (lineseed oil + chalk). This will smoothen the surface but also increase air tightness to some degree.
We build the smaller frame on the ground thinking we could easily lift it up. We ended up asking some extra help to carry it since it was still very heavy. When we got it in place we made sure that both frames were in the correct space regarding to all the walls. When this was confirmed we screwed the horizontal beams from the wall frames against the roof frames to secure everything.
