How to insulate this wall?

[throbscottle]

Bought last year, my 1970's built house has an attached garage. Now discovering the garage is a source of coldness. Dividing walls are single brick, bare on the garage side, plasterboard on the house side.

I'd like to make the walls be more insulated, by attaching something to the garage side. Any recommendations of reasonably priced something to use?

TIA

 

[Jameshow]

I'd use 4" polystyrene cheap but effective.

 

[throbscottle]

Ooohh - I'd better not grind any angles near it then! Or is this special housing grade stuff?

 

[throbscottle]

Jeezy creezy - EPS insulating boards ain't cheap!

 

[throbscottle]

Though I've not compared to anything else...

 

[Phil Pascoe]

I had the same problem. I found my bungalow/garage wall was single block - it shouldn't have passed building regs at the time, it should have been cavity, apparently. Anyway, I got a good deal on 95mm PIR from-
https://www.secondsandco.co.uk/then clad it with 18mm shuttering ply.

 

[Phil Pascoe]

Incidentally, I hung the boards from 95mm timbers fixed to the wall the top as I needed to mount all manner of crepe to the boards so they needed to take some weight.

 

[TomGW]

Rockwool slabs (batts) may be more cost effective than Celotex etc but 100mm white polystyrene, as already suggested, will be a significant improvement. Obviously your garage will be more functional if battened and sheeted over with 18mm OSB.

 

[throbscottle]

Ok that's two things I'd never heard of. But Rockwool slabs are sold more for acoustic insulation?
Need to cover about 12sqM - what's going to give me the most bang for my buck? Prices all look pretty similar between the types...

 

[baldkev]

To be fair, 2" celotex ( pir ) will do quite a good job. Interestingly going double thickness doesnt return double the insulation value.
So batten a frame on the wall in 2x2, with uprights at 2' ( osb will be 1220 x 2440 ) and infil with 45mm pir, then osb it.

Now, i know pir isnt cheap, but its a lot better than polystyrene sheets and not a huge difference.

 

[throbscottle]

Sounds like a plan. I did wonder about diminishing returns of thickness, but no idea of a baseline to even think about that. I'll go from there.

 

[baldkev]

@throbscottle Roald dhal fan?

 

[Stigmorgan]

When the school refurbed the bungalow before I moved in the same issue presented itself, the wall between the bedroom and the garage was freezing cold, the contractor used insulation backed plaster board and it's made I big difference on the bedroom side of the wall.

 

[throbscottle]

@throbscottle Roald dhal fan?

It's true. I couldn't spell "Frobscottle"

 

[throbscottle]

When the school refurbed the bungalow before I moved in the same issue presented itself, the wall between the bedroom and the garage was freezing cold, the contractor used insulation backed plaster board and it's made I big difference on the bedroom side of the wall.

Did they put this on the bedroom side or the garage side?
In my case it wouldn't be suitable on the garage side because I need to attach stuff to it...

 

[Phil Pascoe]

Sounds like a plan. I did wonder about diminishing returns of thickness, but no idea of a baseline to even think about that. I'll go from there.

Look at the price - if you can pick up thicker stuff for a few quid more, do it - you only do the job once. Ensure if you get thick stuff it doesn't impede the opening of any doors.

^^^^ I boarded mine over.

 

[baldkev]

Did they put this on the bedroom side or the garage side?
In my case it wouldn't be suitable on the garage side because I need to attach stuff to it...

I imagine in stigs case, it went inside. To have plasterboard on the wrong side of the insulation ( in the garage ) would put the dew point in the plasterboard.

 

[Stigmorgan]

Did they put this on the bedroom side or the garage side?
In my case it wouldn't be suitable on the garage side because I need to attach stuff to it...

Yes in the bedroom, the garage is bare concrete block inside. Ruddy cold in the winter.

 

[bignik]

I have to mention this as I did a test for reasons of insulating my camper , shredded paper , cardboard or polystyrene beads , wrap in aluminium foil, slide into a poly bag loosely and presto it works and for pennies, I made some up in summer , throw in some drinks food etc at 6am , it was a scorcher of a day , and in the evening my orange drinks were still partially frozen , its all sown to physics. my nephew who is a musician has his studio covered in empty egg boxes for superb accoustics ... just some weird alternatives from a mad man lol

 

[Agent_zed]

Another thing to consider in addition to insulating the wall, if you haven't already, is preventing heat loss from the garage itself. E.g is there a big howling gale coming under the door.

You may also want to look at multi layer breathable foil insulation. Batten the wall - staple on the foil - cover with osb etc. Has the advantage of being breathable and easy to handle.