What's involved in insulating a single skin garage to make it more useable in winter?

[Scully]

17 hours ago, scotslad said:

Must admit I'd just use polysterene rather than the proper insulation just due to costs, does almost the same thing. 

 

I’m afraid it doesn’t. We build houses to some of the lowest thermal loss readings in the country; there simply is no comparison.

[Ultrastu]

3 options of insulation 

Rock wool 

Kingspan/celotex etc

(twice the insulating value of rockwool .so 100 mm of celotex = 200 mm rockwool

tri iso .blanket 

Basically same insulating value as 100 mm of celotex but only 30 mm thick 

 

[figgy]

 Nial I have a hormann sectional double garage door that’s insulated and has rubber seals. It’s good and cuts droughts but it’s not air tight. 

For what your wanting I’d go cheapest insulation  at 50 thick and do the roof and just get a good heater as your not going to keep it fraught free or keep the heat in as you still want it as a garage. 

My garage has 120 mm iirc in the walls then ply sheets and the ceiling is done in twin wall upvc shiplap sheets with Earthwool insulation on top in the loft space. The boiler and and all the pipework zone valves etc is in there and heats the garage to just warm,not enough to sit in and work at a desk but keeps the chill off. 

[Dellbert]

whats the stuff they put on the outside of houses then plaster over ? would this work ?

then just line the inside with maybe 25 mm ??

 

hoping to have the same problem when i move and build a workshop ...

[Nial]

21 hours ago, Ultrastu said:

3 options of insulation Rock wool Kingspan/celotex etc (twice the insulating value of rockwool .so 100 mm of celotex = 200 mm rockwool

tri iso .blanket 

Basically same insulating value as 100 mm of celotex but only 30 mm thick

That tri iso stuff looks interesting, and relativey cheap.

Anybody used it?