Living in Penistone they still get cold, the wood is 35mm thick. I've insulated the roof and floor too. Got an oil filled radiator to warm it up, turn it on an hour before were going in there.
I would back this up 100%. Know the family and the business, fantastic people. Wish I could afford one!!
I'm going to look round when convenient. May even have a go at the flight simulator if they let me (guaranteed to crash if it has a reverse gear. I had a.tiny mishap when I borrowed his van.. Forgave me though lol) But it's in high demand for trainee pilots. Even got an airport lounge and baggage facility for training purposes. The owner Andrew (mi cousins lad) was one of the originators of Hoyland reds Alongside several others of us. Sits alongside us at home games. Bit up and down with the games but his lad still has a ST.
Do it yourself mate, I'm being serious. I bought a cabin from https://www.tuin.co.uk and it arrives pre-cut and ready to assemble, it's like big wooden Lego, and their prices include shingles for the roof. They're as competitive as anything else I saw online and you get the accomplishment of building it yourself.