Its looking like building a custom workshop is going to be on the back burner for a fair bit while I substantially remodel my house. Since I moved I have been workshop less and unable to use any of my machines but I could do with them to help the renovation.
So I'm going to get set up in the garage. It is a double, separate from the house. My old workshop was about single garage size and built by my own fair hands, insulated concrete floor, aircrete walls and insulated slated roof. Very toasty in winter.
This garage is unusual in that for a detached it has cavity walls. I want to tackle the roof first. The tiles are fine if not to my choice. The under felt however is disintegrating and I constantly have bits falling off. Luckily those tiles don't leak so its not a weather problem at the moment.
So my plan is to leave the tiles alone. Which means I'll be leaving the under felt alone until such a time I re-tile the roof.
In order to make the garage a bit more toasty I still want to insulate it in the meantime. I have reasonable access to the underneath. The rafters are 100mm. My plan is to celotex or similar between the rafters then line with ply underneath.
My question is what depth of insulation. I presume I need an air gap so how much insulation and how much air gap in that 100mm? This needs to work with the current under felt and with the new stuff when I get round to re-roofing in a few years.
Opinions on the thickness?
Mark
So I'm going to get set up in the garage. It is a double, separate from the house. My old workshop was about single garage size and built by my own fair hands, insulated concrete floor, aircrete walls and insulated slated roof. Very toasty in winter.
This garage is unusual in that for a detached it has cavity walls. I want to tackle the roof first. The tiles are fine if not to my choice. The under felt however is disintegrating and I constantly have bits falling off. Luckily those tiles don't leak so its not a weather problem at the moment.
So my plan is to leave the tiles alone. Which means I'll be leaving the under felt alone until such a time I re-tile the roof.
In order to make the garage a bit more toasty I still want to insulate it in the meantime. I have reasonable access to the underneath. The rafters are 100mm. My plan is to celotex or similar between the rafters then line with ply underneath.
My question is what depth of insulation. I presume I need an air gap so how much insulation and how much air gap in that 100mm? This needs to work with the current under felt and with the new stuff when I get round to re-roofing in a few years.
Opinions on the thickness?
Mark
