Insulation

[gasman]

I have read many threads on this subject... please don't go all shouty on me for asking the question again but there is quite a bit of conflicting advice.
My workshop is a wooden shed 17"x11". It has no insulation at present. I decided after this cold winter to insulate it in the spring. This last weekend reinforced this idea as it was so hot inside
I have got hold of 50m3 of quite cheap 1 inch kingspan which is enough to do the whole shed. I was going to wedge the kingspan between the 3" joists, leaving an air gap above and then hardboard nailed over. Does that sound OK? If I use kingspan presumably I do not need polythene?
Thanks for your advice
Mark

 

[Anonymous]

Hi Mark,

I've used kingspan style boards to do my workshop (I still haven't finished doing it yet). I've put it in the ceiling and walls with an air gap behind. My workshop stays nice and cool. The other thing which keeps it cool is good overhang of the roof over the windows. The only pain I've found with the boards is measuring and cutting them. It's very time consuming getting them all the right size for the spot.

I don't know about polythene. I was planning on putting it over the insulation boards before I board over with plywood. My concern is that I'll end up blocking out all airflow and will end up with a damp problem. Then I'll have to put vents in to get the flow again.

Dave

 

[jimi43]

Hi Dave

If you are putting polythene as a moisture barrier you are correct...it needs to be on the inside of the insulation.

If you barrier right over the air will circulate between the insulation and the wood if you leave a gap all the way to the eves...the idea being you get a crossflow of air whatever the wind direction...leave the eves open.

Jim

 

[StevieB]

Consider OSB rather than hardboard - will let you put shelves etc wherever you want. Hardboard will not be strong enough to screw into.

Steve

 

[jimi43]

Consider OSB rather than hardboard - will let you put shelves etc wherever you want. Hardboard will not be strong enough to screw into.

Steve

+1 DAMHIK

 

[OPJ]

However, hardboard is fine for covering the inside of your roof (less weight, cheaper, etc.). If you go for the white-faced stuff as well, it'll brighten up your workshop, too.

 

[Anonymous]

Jim,

cheers for that. I need to cut holes in the eaves as I'd previously blocked them up.

As for the airflow I meant inside the workshop, not in the walls. Loads of people on the forum have insulated their workshops like mad and then discovered the machines start rusting.

Dave

 

[gasman]

Thanks everyone for the advice. OPJ great tip about the white faced hardboard. I may not bother with anything apart from the insulation on the walls at first as the insulation will stay where it is very easily if I cut it correctly - that way I can just mount shelves etc into the joists as they are at the mo
Thanks again
Mark