What is the best way to insulate a 1930s brick house from the outside?

Stephane Marcotte Sept. 2, 2021Updated: Sept. 9, 2021


I have a semi detached house in Toronto Canada.

The house built in the 1930's is double brick wall. The house is original and has little to no insulation right now. I want to insulate the house from the outside with as high R value as possible.

After insulation I was thinking James Hardie siding.

Apparently brick is a problem because you need something to fasten the insualtion and siding to and apparently James Hardie siding is heavy I have been told.

Rigid foam or Spray foam?

I need advice on best practice.

Thank you


Toronto Ontario 


Responses (2)

Stephane Marcotte 1 year ago

Hello Emmanuel, thank you for responding to me. Since writing on this post I have been shopping around for rigid foam installers and I have a quote for 2 inches of rigid foam Isoshield sheets (total of R10) with Hardie siding applied on top of that.

To answer your question, I have lots of room between houses or "setback".

The Thermal walls are definitily an option I did not know about.Crazy how thick you can go and how high R value you can get with this.  

Thank you very much for answering my post.  

Best regards