I used Gyproc plasterboards for the inner walls and ceiling of my workshop for one very good reason: they are fire-proof! Okay, special care has to be taken when fastening stuff to Gyproc, but I found a glue gun does a good job if the glue is well spread. Insulation in the ceiling is almost 10" fibreglass batts,, and in the walls 4", so the heat pump has a very easy job to keep it warm in winter, even at minus 20 ℃ . That last image is a Xmas greeting from down under, the Xmas spider (Austracantha minax). Had a fair few of them around the house at yuletide in WA. Very spectacular, and not poisonous.Hi just had a new workshop built and I'm now looking at insulation and cladding the interior. Does anyone have suggestions on materials for either please?