I'm not sure if im embarrassed about this last project or not
It looks simple but is actually made in the same manner that you would build a timber framed house.
Stud partitions giving a depth of 2", with multiple layers(5) of foil backed insulation in the spaces.
6mm internal ply cladding.
Outer consists of studs,covered by a vapour barrier,covered by 18mm osb,covered by roofing felt, which is stuck on using bitchumen based adhesive, which also adds to the overall waterproofing.
Lid is hinged on, but is of sufficient weight(18mm pine boards, with cross members providing an overhang, also coated in bitchumen, varnished internally
Base is 18mm osb,then 5 more layers of insulation, covered by 6mm ply covered by melamine to provide a weatherproof barrier, although within a few months the soil beneath will dry out completely. It also stands on 4x 3" thick legs.
Internal flooring is bare osb, covered by 10mm dual sided closed cell foam from a camping sleeping mat. Contact adhesive to the osb.
3 windows of differing sizes(2 sides,1 rear) lined and framed in mahogany, with 8 layers of waterproof paint and 5mm perspex for the glass. Inside face of the external window frames are also bitchumen coated to prevent water ingress onto the back of them due to the rough nature of the felt
Lower protective external cladding in mahogany also with 8 layers of the same paint.
Standard cat flap at the front.
Cannot tell if the little blighter has used it yet
Im hoping he will in heavy rain and get used to it from there. I'll stick in some more of his own blankets to help persuade.
I know it looks a bit rough after a week out, but its very solidly built, and i think considerably more wind and watertight than your average outdoor structure,sheds and the like.
I've still to add a ventilation grille, just to prevent any moisture build up.
) this cherry is an absolute pain to hollow end grain, anyway I got most of the way down and instead of stopping to sharpen as I was getting g a few little catches I decided to go for one more pass, big mistake, got a big catch that caused two parallel cracks running top to bottom, to say I was pi$$ed is an understatement and I must have used every profanity I could think of. I decided to fill the cracks with glue and try to pullt it all back together but I couldn't find my big jubilee clips that would have done the job perfectly so had to use tape which brought the rim back together but didn't do a great job in the middle 
