Rigid foam / Discussions

Should I install a poly moisture barrier before the rigid foam board against a basement wall?

...rigid XPS foam board insulation held in place with the special plastic pegs (since the poly will not allow adhesive to affix it to the wall), blue sheathing tap...

Posted by DONandCATHY Crenna Dec. 14, 2020, 2:21 p.m. Basements improvements 2 Responses

Can you add exterior rigid foam insulation (e.g. EPS) with replacing windows?

We are contemplating an energy retrofit to several 1960's chalet style cabins in Northern VT. Budget matters and the windows of the cabins are in reasonably de...

Posted by Peter Milliken Nov. 9, 2020, 9:13 a.m. Wall assemblies - renovation 0 Responses

Can basement walls to dry to the inside with foam board?

...foamboard to my basement foundation walls. From all of my reading it says that your basement foundation walls can only dry to the inside. If I put foamboard on ...

Posted by Tim Hanrahan Aug. 20, 2020, 12:34 a.m. Basements improvements 6 Responses

Can Rockwool be installed over Type II EPS?

...Foam Insulation & Styrofoam Sometimes adding XPS or EPS rigid foam to the outside of a house can cause problems since it can trap moisture. That said, it is m...

Posted by Brian Bonnell March 30, 2020, 11:04 a.m. Wall assemblies - renovation 1 Responses

Heco topix screws - which type should be used for attaching insulation outside a house?

Attaching battens through 4" EPS foam external insulation, should Therm Insulation or Stainless screws be used? Is it necessary to have the double thread desig...

Posted by Mike Taylor April 7, 2020, 4:45 p.m. Materials and resources 2 Responses

Do you have an updated recommendation for attaching exterior mineral wool insulation?

...rigid foam insulation panels ThermalWall is an EPS rigid foam panel with a metal rail embedded in the middle of the panel allowing it to be attached to the exte...

Posted by Fred D Aug. 31, 2020, 1:07 p.m. Wall assemblies - new construction 1 Responses

Can you spray foam a house from the outside?

...rigid foam with foil directly under the siding. Someone recommended removing the sheathing and doing spray foam from the outside. It seems we could also drill h...

Posted by Joan Lawrence July 11, 2019, 7:17 p.m. Wall assemblies - renovation 3 Responses

I want to insulate the outside of my house, which type of insulation do you think is best?

...rigid foam panel and I don't want to choose the wrong one, which do you recommend and how much will I need? Thanks, Michael. When I drive by houses doing exactl...

Posted by J. Ferguson Nov. 15, 2017, 10:34 a.m. Wall assemblies - renovation 12 Responses

Should a Vapor Barrier be installed over Exterior Grade Plywood?

...Rigid Foam insulation. In the future I may add A/C to the cottage. Do you believe a Vapor Barrier to be necessary? Thank-you Michael Vapor barriers can be a pro...

Posted by Michael Klauck March 6, 2020, 1:24 p.m. Air and vapour barriers 1 Responses

What is the best material to use on top of plywood for water proofing?

...Rigid Foam, Delta Dry etc. For help choosing a weather barrier for the exterior of a home see here – Choosing a house wrap, which is best? In our 2015 LEED ...

Posted by Babak K July 27, 2020, 12:22 a.m. Air and vapour barriers 3 Responses

What is the best way to deal with a drop ceiling in a high humidity room?

...rigid foam insulation and then faced fiberglass batts and then plywood subfloor of the outdoor deck. The rigid foam was not sealed (no air barrier) and this p...

Posted by steve Roberts Dec. 24, 2019, 8:01 p.m. Walls and ceilings - interior surfaces 1 Responses

How do you insulate a crawlspace with dirt floor?

...rigid foam panels on the concrete block walls (2 inch) The cottage is 900 square ft. To complicate things, we have just made a 400 square foot addition on concr...

Posted by sal Bellicoso Oct. 30, 2019, 4:56 p.m. Crawl spaces 2 Responses

What is the best exterior Wall and Roof Rigid Insulation for a barn renovation?

...rigid insulation. 1/4 " Plywood sheathing attached to the Girts, Rigid Insualtion, rain screen (Tyvek?) 2 X 4 or 1 X 4 Strapping screwed through the insulation ...

Posted by Ron Busch June 27, 2020, 3:50 p.m. Wall assemblies - renovation 1 Responses

Can you install foam boards directly against basement walls?

...rigid fome to Install two inches of rigid insulation board directly against concrete. A mold expert told me to put the board on top of the framing, not directly...

Posted by Ted Gorab Oct. 3, 2019, 6:09 p.m. Basements improvements 7 Responses

How do you make an airtight house envelope?

...rigid foam is not something I would rely on as an air barrier, and even spray foam can sometimes shrink and crack, leaving gaps that can lead to air leakage. Ar...

Posted by Valeriy Kraydman Dec. 1, 2020, 2:52 p.m. Air and vapour barriers 1 Responses

What do you think of Legalett Wall Insulation?

...foam product can give it a bad rap in green home building circles, but we think that EPS insulation may be the best option in the long-term, read more here – ...

Posted by Igal H Aug. 19, 2020, 3:52 p.m. Walls and Roofs 1 Responses

Why is there condensation in between 1.5" polyiso board and roxul insulation?

...foam. In front of the wall I frame to buy for walls and insulated with Roxul insulation Batts I went to go do some electrical work today and pulled back a bath ...

Posted by Tyler Norrie Feb. 9, 2021, 2:32 p.m. Basements improvements 0 Responses

What is the best way to insulate rim joists with EPS and batts?

...rigid EPS and see if you can make it continuous with the wall insulation below it. If you install several layers of EPS it will function just like a SIP wall, t...

Posted by Steve J July 18, 2019, 3:53 p.m. Basements improvements 1 Responses