We don't have many brick homes around here in central Vermont. I recently visited a one-story ranch home that was built with exterior walls of hollow core CMUs (concrete masonry units), a brick…Continue
"Thank you for your advice Sean. The cellulose will be removed very soon and I'll make sure they clean it up properly. I already aerosealed my ducts so that should help tremendously. I'd like to give it some time before…"
"A few quick thoughts - main issue is in the summer with open cell? If so I would strongly check into that due to moisture drive is inwards during the heat of the day & many times people notice an odor it is due to improper mix
"Good point Brad. I wonder if there is something IN my attic that was not detected and is now encapsulated in the attic, in the cellulose?
HMMMMM..... A lot to think about. Thank you again for being a sounding board in this thread.…"
"Jan, you bring up another possible source of that bad odor, the Icynene. If the mixture of Part A and Part B is not in the proper ratio, you will get chronic out-gassing of odors. I previously mentioned the possibility of Ammonium Sulphate in the…"
"Which is why I always measure bath fan flow (with the Energy Conservatory pan and DG-700 meter) and try to verify where and how it is exhausted.
I have seen brand brand new Panasonic bath fans vented with plastic flex duct into voids, kneewalls and…"
"Brad - thank you for your insights. I listed a home for sale with that Whisper Green fan - loved it! I'll check it out. THANK YOU!
I appreciate all the insights I can get.
As a realtor, having good sources of…"
"During our hot summer months, the odor that is created in my attic is noticeably bad and it infiltrates my house via the attic access in my master closet - of all places to have an odor created! I've lived in the house now for 2 years and…"
"Good points John. As a contractor, if a client provides a product (such as a bath fan) and asks me to install it, I usually will but with the caveat that I provide NO warranty of any kind.
I am a big fan of the Panasonic Whisper Green fan. You can…"
"I would not 100% of the time recommend removing the fibrous insulation on the attic floor with the roof deck is insulated. I'm not sure from your description that is your odor problem. I am questioning if your house is tight enough…"
"Thank you John! That's my plan, swap out the fans first. Appreciate the advice!
As a realtor with 2 designations in green building, we still have to rely on others to do the work. Like most consumer products, i…"
"Are the bathroom fans ducted to the outside or into the attic?
If they exhaust outside, *Not* into the (now sealed) attic, great. Replace your bath fans with a new one. Get an 80 CFM model ( to still move 50 CFM from the…"
"The air test was done prior to Aerosealing and tests were fine. No drywall was removed so the vermiculite was encapsulated.
Great comments about air quality. I'll check the bathroom fans.
The cellulose is definitely very old and…"
"Jan- If you had a blower door test (BDT) done and there was vermiculite in the hollow cores of the CMUs, then I wonder if any asbestos fibers in the vermiculite could be sucked into the house during the BDT. That aside, if air sealing work was…"
"I had a blower door done on my 1979 block home but didn't know I had that in the walls. I must have it another auditor told me because my house is now tighter than I expected it to be.
I also added Icynene under the lid of the roof, 16…"
"For John N.- The homeowners had the house gutted and renovated. They found vermiculite leaking from a couple of holes in the CMUs. They also believe that the vermiculite can be seen at the top of the CMU walls in the attic. They also told me that…"
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