Green Homes News

Coalition of organizations has urged the agency to require latest codes for all new homes with mortgages backed by Fannie Mae and Freddie Mac

When 2021 IRC raised insulation levels it did not make a corresponding increase to the condensation control insulation levels. Consequently 2021 has lower ratios compared to 2018. Does that mean…

I have a house in Florida (ASHRAE 1/99 temp range, 46-92 F) that previously had a ventilated attic. I had plans to turn it into a sealed attic with spray…

Location Zone 3A OKC, OK. House constructed 1979. Wall details-5/8 Sheetrock-2/4 Wood Stud Fiberglass batt (Unsure if faced or not. I know areas I have demoed in interior walls separating the…

Tools for carbon credit buyers looking for vetted data on where to invest

Hi Guys,I am building a PHIUS-certified house in Canada as a self-build project.I am finalizing the design for the window installation and I am encountering some difficulties.My wall is about…

IRC2018 defines an insulation ratio for condensation control in unvented roofs.  In note B of Table R806.5 it says, "Alternatively, sufficient insulation shall be installed directly above the structural roof…

I am working on designing my house and the garage will share one wall with the main house. The main house will have all unvented attics. The obvious answer is that…

Hi, I am hoping for some advice on insulation questions. I live in coastal (wet) South Central Alaska, zone 6, and am building a 1,200 sq ft, two-story house (one…

We live in a large (3000sq ft), old (1907) home in Northern Kentucky. Our house has three finished levels and an unfinished basement. In the summer, our A/C (Daikin Fit…

Our house's basement has an original cold war era bunker with concrete floor, ceiling, and walls, and no insulation or heating.  The bunker has a door connecting it to other…

We have a 1925 colonial in New England (Zone 5), and we had cellulose blown in most of the walls when we moved in. In one small bedroom, they ran…

Should you use a polyethylene vapor retarder on the interior of a foundation wall?

https://buildingscience.com/sites/default/files/migrate/pdf/PA_Foam_Shrinks_FHB.pdfIn this FHB article, Lstiburek writes:"Window film is a poor substitute for the right glazing at the time of the deep-energy retrofit, we used the best windows we could buy:…

I've been asked to work on this house and I'm mulling different ideas to improve the energy efficiency while maintaining the character.It was built circa 1967. It was built as…

Can anyone help with debug of a mini split problem ?MSZ-FE18NA/MUZ-FE18NA, Single Head, Hyper HeatI have had a long list of frustrating experiences with local service folks over the years.…

Hey All,Building a house on a steep lot in CZ 6. The uphill-side of the home's basement concrete wall is the basement is the actual basement wall and will be…

My roof assembly is 2x12" rafters.I want to use r40 Batts@11.25" so I need to increase the depth to allow a 2" vented channel.All the details I've seen here add…

Hello community,I live in Northern California, Zone 5, in a dry climate, hot dry summers, and rain/snow in the winter.  Our basement and crawl space is not heated but the basement…

Hope everyone is well. Always found good advice on this forum so figured I would ask. I’m in the planning phases of a 20x14ft rear 2 story addition (full basement)…