GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

ERV or HRV? Need help for musty cabin

dz6ntgCWpa | Posted in Mechanicals on

I have a 1,600 sq. ft. log cabin located in New York (Catskill region) built in 1972. The cabin is used part-time, mostly weekends — sometimes a week at a time.

The cabin always has a musty smell. I need to choose the best way to improve the air quality. This home can be shut for weeks at a time. In the summer I run a dehumidifier in the basement 24/7 at 65%.

In the main part of the house when I’m there I open windows and run fans to stay cool and move some air. I rarely need AC. The only time I use AC is when its real hot and high humidity 3-5 days. The cabin is in the mountains. The AC are window units.

When I’m not there I leave some windows open and a widow fan on low exhaust. Mold and moisture is an issue. This fall I spent 3 weeks cleaning and sealing the logs, interior and exterior, so I think I’ve got the mold cleaned and the logs sealed.

I hope to help the mold and moisture issue with the ventilator. In the winter I use the cabin 1-3 times a month. We use a wood stove to heat most of the house and electric if we need it.

When I shut down the house, the only heat I have is in the basement set at 45 degrees. The windows are shut. I leave a ceiling fan on to move some air.

It gets cold in the house so the RV will be running with no heat a lot of the time, and in the summer with no AC .

My goal is to have the best air quality possible, nd not bust the bank. Is an ERV or an HRV the right thing for this cabin?


GBA Prime

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.


  1. wjrobinson | | #1

    I think you need to find your moisture source and remediate it. And find the mold and remediate it. Then lastly you can install an HRV such as the Panasonic unit which is low cost if that helps.

    Read up on wet basements, and more. Older log homes around here are wet at the bottom log area and rotting out there along with harboring mold etc. Also prone to problems under windows and where decks attach.

  2. GBA Editor
    Martin Holladay | | #2

    I agree with AJ that you have a moisture problem, not a ventilation problem. You need to address the source of the moisture.

    Your current approach (simply increasing the ventilation rate -- "When I'm not there I leave some windows open and a widow fan on low exhaust") may, in fact, be counterproductive. If the cabin is cool, and you introduce exterior air which is hot and humid during the summer, you may actually be adding moisture to your house.

    If you have been running a dehumidifier 24/7 in the basement, my guess is that your basement is damp, and that is the source of the moisture. The usual remedies apply: change the exterior grade around the perimeter of the foundation so that the grade slopes away from the house; add roof gutters if necessary, and install conductor pipes to convey the roof water far from the foundation; install poly on your basement floor if the floor is dirt; consider installing footing drains drained to daylight if necessary, or interior French drains leading to a sump equipped with a sump pump.

  3. user-659915 | | #3

    In addition to the excellent advice above I'd ask: is your house surrounded very closely by trees? At least in our neck of the woods (ha!) this condition often brings additional mold/humidity problems - especially with pines. Not to mention that roots can disrupt drainage patterns and compromise the integrity of the foundation wall.
    As an aside: a while back we found that a crawl space water problem stemmed from a dogwood root that had not been removed when the foundation was dug. After the stump rotted out on the exterior and the root with it, it formed a perfect funnel and pipeline to the interior, below the crawl space footing and into the partial basement. When we cut into the crawl space dirt to enlarge the basement area we found that after a heavy rain the cut end of the 'pipeline', previously blocked with enough clay to produce only seepage, would discharge water into the interior like a faucet.

  4. dz6ntgCWpa | | #4

    thanks guys
    I think the moisture in the summer is due to lack of sun ,from trees and there is a hill on the south side of the property . I will try to do some tree work this spring. The basement is not the problem .the dehumidifier is on 24/7 but just runs till 65% r/h [ sorry i did not make that very clear] when we first bought the cabin I put on a new roof ,put in 6 sky lights [no leaks] did a footing drain on one side of the house and had a mold man do a job in the basement.I did all the work my self except for the mold job.[he used calbrite]I have not seen any mold come back.[7 years] last fall i cleaned the whole inside of the cabin with 3 men + my self with a concentrated hydrogen peroxide and a lot of scrubbing at the same time i treated the out side with the same hydrogen peroxide and power washed and finished with a sickens sealer the inside with a water base log sealer .and then put in new get the picture. a lot of work.but we love this cabin .and i don't mind the lets assume the place is mold free for now . whole house dehumidifier,a/c,erv,hrv,heppa need clean air for all seasons thanks for all your time Evan

  5. Erikpry | | #5

    Greetings Evan,

    I have a very similar problem with my cabin that is also in the Catskill region. The musky smell continues to be an issue even after all of my attempts to remove excessive moisture through ventilation, dehumidification, and sealants/barriers. Have you managed to find a solution that has been successful for you?

  6. GBA Editor
    Martin Holladay | | #6

    There must be source of moisture in your home. But it's impossible to identify the source of the moisture without more information or a site visit.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |