Hi all, I'm looking for a bit of advice on how best to insulate an unused stable I have inside my shed.
2 x external walls and 2 x internal walls are 6" block on edge and external and internal walls are plastered
Stable is 15ft x 10ft and 8ft high (stable itself isn't roofed separately - it is open right to apex of the shed)
I want to use this for storage for things I want to move out of the house that I don't want getting damp and tools that are starting to rust in the shed
Here is what I was thinking:
Floor:
1200guage dpc
4" x 2" frame (studs at 600mm centres)
100mm PIR insulation in-between frame
18mm OSB board screwed to frame
Walls:
3" x 2" battens with dpc glued to wall side of batten - battens at 600mm centres
100mm PIR insulation (screwed to battens just to hold in place until OSB board fitted)
11mm OSB board screwed through insulation into 4" x 2"
(Would I be better fixing a 4" x 3" timber stud to the battens and insulating in-between the studs and then OSB board screwed into the stud?)
Roof:
One wall is 8ft high, other 3 walls are higher as part of main shed
But I can run joists from the 8ft wall to a purlin on one external wall (span is 10ft)
6" x 2" purlin on top of 8ft internal wall
6" x 2" joists (10ft long) over to external wall (there is already a purlin at right height)
100mm PIR insulation between joists at 400mm centres
11mm OSB board on bottom of joists
18mm OSB board on top of joists (for additional storage on top)
Would an air-tightness membrane taped the whole way around the room after insulation is fitted before OSB board is fitted be complete over-kill or not make any difference to how warm the storage room would stay?
If it would make a difference, I'd take the cost and effort of doing it - I just don't know if it's worth it.
Any advice on above would be appreciated.
Thanks.