Search the Community

Could anybody advise on what thickness of double wall polycarbonate sheet would be best to insulate the ceiling and walls of my greenhouse over winter. Greenhouse is 8' x 12' and I've fitted some tube heaters but need the insulation so they're not running all the time. I'd like to keep temperatures 10C min for my N maxima, Pings, Utrics & Droseras. VFT's & Sarrs will be moved to a mini greenhouse where I'll let the temps go lower than that. I'm in Derbyshire in the middle UK so winters can go down to -5C or so, occasionally a bit lower (2010 being the exception at about -20,if that happens again I'll take the plants indoors). I've seen 10mm sheet and read on CPUK of people using 4mm but I've never used it before so I'm not sure of the pros and cons of each. Any recommendations would be appreciated. I'll be removing the sheet from the walls once winter's over but might leave the ceiling sheets in place to provide a bit of shading (semi-opaque sheet for this part). Thanks Gaz