Insulation & Vapour Barrier
Insulation turns a seasonal shelter into a year-round cabin. For stud-framed walls, mineral wool between the studs is the simplest and most effective approach. A vapour barrier on the warm (inside) face prevents condensation in the wall.
Mineral wool (Rockwool or Knauf) is the best all-round choice: fire resistant, moisture tolerant, easy to cut, and affordable.
The vapour barrier goes on the WARM side (inside face of the insulation). Getting this wrong causes condensation and rot inside the wall.
Don't compress insulation to fit — compressed insulation loses its thermal performance. Cut it accurately.
Tape all vapour barrier joints with specialist vapour tape — this is what makes it actually work. Gaps defeat the purpose.
WALLS: Cut mineral wool batts to fit snugly between studs. Friction fit, no gaps
Ensure insulation fills the full depth of the stud cavity
Staple a continuous vapour barrier (polythene sheet, 250mu) across the inside face of the studs
Tape all joints, overlaps, and penetrations with vapour tape
FLOOR: Install insulation between floor joists (support with battens or mesh below)
ROOF: Insulate between rafters or above ceiling joists — ensure ventilation gap at ridge
Seal around all penetrations — pipes, cables, flue — with appropriate sealant
Install internal wall boarding (plywood, plasterboard, or tongue-and-groove) over the vapour barrier
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