Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 ahowell 95
6 KnowledgeBase 95
7 skbloom 80
8 Guest_98024861 70
9 Guest_9311297 70
10 Guest_9400529 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 9/12/2019

Best way to add insulation to flat roof house without attic (Mckay home)

I live in a McKay home with flat roof and concrete slab. It gets very cold during winter and the heat doesnt stay inside for long. Its not a big problem during summer, as heat quickly dissipates.The previous owners changed the roof (roof is in a good shape) but did not add insulation.

I am contemplating adding insulation to the roof. I have got quotes for 3 different methods.

1. Spray Foam insulation - Apparently providers very good insulation but can have leaks and other issues.
2. Put a layer of ISO board in between the roof panels
3. Put a layer of radiant barrier in between roof panels

I would like to hear some expert opinion comparing the three options and advice me on which one is the best for keeping the heating cost down. I would also like to make sure the solution involves less (ideally none) maintenance and long lasting benefits (at least 10-20 years).

Do you have the same question? Follow this Question

2 Answers


Am old home improvement contractor not an insulation contractor. From my weatherization experience once roofing has been replaced any sheathing or radiant barrier is not a viable solution. Spray foam must have drywall (or other material inbetween) it and living space. By all means go that route if possible. High R values, an to my knowledge- an airtight barrier is a given. I was a weatherizer when Carter was in office. Radiant barrier needs dead air space and no dust to work.

JIm Casper

Omaha Ne

Answered 1 year ago by JimCasper


When i say spray foam insulation, I am talking about "Spray Polyurethane Foam" with a protective coating on top (for waterproofing) thats typically used for roof. Is that way more superior to ISO board and radiant barrier ?


Answered 1 year ago by ursvasan

Related Questions

Terms Of Use
Privacy Policy