Basement air sealing - unsure locations. - GreenBuildingAdvisor
Summary
The article discusses three specific locations in a basement where air sealing is uncertain, seeking advice on best practices for sealing these areas effectively.
Why It Matters
Proper air sealing in basements is crucial for energy efficiency, moisture control, and overall indoor air quality. Understanding the best practices for sealing can help homeowners and builders improve building performance and reduce energy costs.
Key Takeaways
- Sealing the bottom plate of dividing walls can enhance energy efficiency.
- Consider the implications of sealing around plumbing fixtures like toilets.
- Addressing voids in hollow concrete blocks is essential for effective air sealing.
Basement air sealing – unsure locations. BigSaveDave | Posted in General Questions on February 17, 2026 11:29am Hi, I have 3 locations that I’m (mostly) unsure about what to do with. I cant seem to get the uploads to work, so here is an imgur link: https://imgur.com/a/jcoXSvp 1. The bottom(base?) plate of dividing walls. I know if this were the top plate in the attic it would 100% be sealed. Is it ok to be sealed from the basement? I attached a picture, it’s the one with the cobwebs and the partial electrical panel (2 and 3) 2. The bottom of the toilet.. Is this ok to air seal? I have spray foam I’m using. Should I use a foam board and foam it in place instead? 3. I have several of these hollow concrete blocks with large voids in them. What do I do with these? picture 4 and 5 Answer GBA Detail Library A collection of one thousand construction details organized by climate and house part Search and download construction details Join the leading community of building science experts Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field. Start free trial Related Questions Advice on air sealing locations Vent locations Intake air locations Basement air sealing Replies Log in or create an account to post an answer. Sign up Log in
