Results 1 to 5 of 5

Thread: Green Mold

  1. #1
    Join Date
    Feb 2006
    Location
    RedWing MN
    Posts
    110

    Green Mold

    I have not been involved with the causes for green mold before and now find myself indirectly attached to a house that has it. The parsonage built by the members in 95 was lived in until 07 and then sat empty. 18 months ago we brought a new pastor in to live there. A month ago they were complaining of being sick a lot and they found high levels of green mold in some but not all of the bedrooms. A mold abatement team came in but thought that there is a problem larger and want to call in an engineer to study the problem. Of course the insurance company is involved now so I have been just watching from the sidelines.
    The house built in 95, has ladder truss floors, vinyl siding with an asphalt shingle roof. Decent insulation with poly covering the walls before being sheetrocked.There is a Lennox F.A. system, Lennox HRV taking air from the bathrooms and kitchen. While there is some little things that could be fixed on the system that I saw I'm at a loss as to the mold being in weird places. Most of the areas are on outer walls in the corners by the baseboard including the baseboard. Never over 18" froom the floor. It is in the upsairs bedrooms on opposite corners of the house and one bedroom down stairs. There is some in the closet by the front door at the other end of the house, which had it's register closed. The HRV is used on timers for when the bathrooms are used. The A/C was off and the windows open but it did not feel too humid. This was just a walk through, I'll have to go back with my psycometer some time but with the windows open it might not be accurate. It has been raining a lot here in Lake City,MN. They have been running a dehumidifier in the basement.
    I think this is a lack of air flow problem but would like input on this as I have not encountered it before, my time now is mainly in refrigeration and teaching of it.
    What do you think? I'm not sure an engineer is going to know what to do.

  2. #2
    Join Date
    Jan 2005
    Location
    Emerald Coast
    Posts
    965
    Vacant buildings, without adequate heat in the winter, will often get moldy.

    Be glad you caught this condition before it gets any worse.

    ...
    Do not attempt vast projects with
    half vast experience and ideas.
    ...

  3. #3
    Join Date
    Jun 2003
    Location
    Madison, WI/Cape Coral, FL
    Posts
    6,643
    Mold locations indicate that condensation is taking place during cold weather. If the house was closed for the last year without heat or ventilation, moisture may have condensed last fall as the home dried down from summer moisture. After mold grows, it remains until removed. Another common spot is the rim joist behind the insulation at the end of the cavity.
    Solution is clean as much as possible, turn the HRV to low full time, and Maintain <50%Rh through the home including the basement. A dehumidifier in the basement does not mean that the space dry year around. There are times of the year that you need whole house dehumidification. With adequate fresh air ventilation, there are times that you need to remove 70 lbs. of moisture a day. Get a powerful dehumidifier like a 90-100 pint per day Santa Fe whole house dehumidifier. What you do, <50%RH throughout the spring/summer/fall and avoid condensation on the windows during cold weather.
    After cleaning the mold from behind the insulation at the end of the joist cavity, re-insulated with foil faced foam and caulk the edges to seal from basement air. check for water leaking into the basement during heavy rains also. Any carpeting on concrete?
    Regards TB
    Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
    Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
    Use +Merv 10 air filter. -Don't forget the "Golden Rule"

  4. #4
    Join Date
    Feb 2006
    Location
    RedWing MN
    Posts
    110

    mold

    Yes there is carpet on 90% of the basement floor. I need to get back over there to check the RH. to see where it is at.
    Thanks

  5. #5
    Join Date
    Jun 2003
    Location
    Madison, WI/Cape Coral, FL
    Posts
    6,643
    Where the %RH is right now does not mean much. Were %RH was and were %RH will be critical. With carpeting on concrete <50%RH is critical all of the time.
    Regards TB
    Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
    Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
    Use +Merv 10 air filter. -Don't forget the "Golden Rule"

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event