Replies

1. 
   calvin | Jan 27, 2023 08:38am | #1

   Since there’s been no reply.
   Have you had this mold tested?

   Mold maybe, but there’s another possibility.
   In cold climates we’ve seen dark lines on walls at the stud locations. Usually not mold but “dirt “ in the air sticking to the cold studs. Often higher up as that’s where the heat and higher humidity sits.

   Heavy smokers or dust etc add the particles while lots of plants or aquariums off gas the moisture which condenses at the cold stud locations.

   What is your humidity reading and is there not much air movement in the rooms.

1. 
   Meaford | Jan 31, 2023 06:51pm | #2

   Tnanks for the reply Calvin, and sorry for the delay replying, I was taking your advice on checking the humidity. At the mold spots it was between 61-64% rh, and other areas were 58ish. The temp in our house is about 21C.
   The air doesn't feel stagnant but some rooms will go hours without people in them but all rooms have vents.
   I haven't had the mold tested but will look into it.
   I didn't mention it before but the ceilings all have a popcorn finish-not sure if that matters.
   Have you heard of a paint I could apply on the ceiling that's acts as a vapour barrier or something I could add to the attic? Would more insulation help in your opinion?
   Thanks again for the help.

1. 
   calvin | Jan 31, 2023 09:54pm | #3

   Here in NW Oh., comfortable percentage would be more like 38%rh.

   Enough for some condensation on the bottom sash on cold nights.

   Cold spots (studs and plates is where the “dirt/grime” collected) due to higher moisture content on cold surfaces. Interior temperature didn’t really make a difference.

   I would non scientifically say that the same could happen with mold I guess.

   There is paint they claim is a moisture “blocker” but I don’t know as to its mold “proof-ness”. The direct cold transfer blocking is your best bet. That and lowering that humidity. Do you have fish tanks or a lot of plants?

1. 
   Meaford | Feb 06, 2023 09:30pm | #5

   I think you're in a similar climate as i am (Ontario, Canada) so my moisture level should be similar to yours im sure. I have quite a few plants but we got rid of the aquarium last year. I've been running a dehumidifier which has helped but it fills up overnight so I started wondering if it would pull moisture into the house- probably highly unlikely. We had an energy audit done last April and moisture was brought up at that time as well. I think the house is "tight" or something along those lines. I was wondering if adding more insulation in the attic would help as unclemike42 mentioned so I think we'll try that and look into the paint.
   Thanks again, you've been a big help. Cheers.

2. 
   unclemike42 | Feb 01, 2023 12:55am | #4

   More insulation in the attic, above the wall, is going to reduce the heat loss in those upper corners. Baffles will help keep air circulation from eaves to vents above, and let the roof decking dry. This is also the first remedy for any ice dams.

   If you cannot get to the edge of the attic, you may want to call in a local insulation contractor for an estimate.

   There is also something going on with all that moisture in the house.

   You can buy paint primer that is formulated to act as a vapor barrier.

3. 
   Meaford | Feb 06, 2023 09:34pm | #6

   Thanks Unclemike42. I'm going to look into renting a machine from Home Depot for blowing in insulation and see if I can take care of that and the baffles myself. Try to save money if possible. I'll do more research on the paint and see if it'll help. I'd really like to get rid of the popcorn ceiling before doing that though.
   Take care.