Latest blower door test
![](https://secure.gravatar.com/avatar/0130c3e37bda4f513b005b952237c7b0?s=52&d=https%3A%2F%2Fimages.greenbuildingadvisor.com%2Fapp%2Favatars%2F200x200%2Fn.png&r=g)
Zone 5, Coastal CT.
I requested a blower door test pre-drywall to see how well we might have done with the renovation of our 1850’s modified cape. The final test for the CO will come later.
I know many of you dislike CCSF but I chose to use it for the older portions of the house and the basement walls. For the new construction I used CCSF flash and rock wool batts.
Per my energy consultants recommendation I also used Aero Barrier before we installed the rock wool. He had evaluated the house before we started any demolition and construction and we had tested at 15 ACH50 in 2022. 15!!!
This morning we tested at .88 ACH50, more than 15 times better than pre-construction. He told me he has never gotten a number that low for a renovation. Yes, there’s an ERV being installed.
I wonder what it will be after we’re finished? I was hoping for under 2.0, but am happy with .88!
Nick
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb1.png)
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb2.png)
Replies
Nick,
Nicely done!
Well done.
Walta
crazy difference. to what extent was the remodel? did you replace siding, sheathing, add any type of WRB, etc for the existing portion?
I tell people, "pick anything, we replaced it."
It was a gut to the studs renovation with new siding, roofs, windows etc. Some new additions. All new plumbing, electric, HVAC. You name it, we replaced it. No new sheathing on the old portions but Blueskin everywhere.
The Aero Barrier was expensive and messy but very effective. We went from 183 square inches of leaks to 19 square inches.
pretty good!
were there any surprising areas out of those 164 square inches that had a bit of aerobarrier build up on? or was it all as expected?
Can't really say. The Aero Barrier guys went around and used canned spray foam where they spotted leaks during the process. They also did all around the windows. That I did not expect them to do that.
You did it all perfectly. Good job.
I learned a lot from all you guys on GBA. Thanks to everyone for their input!