Mold eruption

[Gooster]

Hi everyone. Within the last month my boyfriend installed a wood burner in the basement. We love the extra warmth it is providing. I have owned the house 10 years, and once in a while a couple of the walls in the house have mold where the wall and ceiling meet, some in the corners, and some at the baseboard level. All exterior walls. They were always cleaned with a bleach mixture and never seen from again for at LEAST a year. Since we started the stove, its out of control. We wipe up the ick, and within 2 days its back. Is this something common from introducing an extra heating source into the home? None of the walls are soft or flaking. I do have A LOT of house plants. The house temperature is generally set at 61. The wood stove is small, and has kept the house around 65. Any thoughts?

 

[blueguy]

Mold on exterior walls generally = too much humidity, poor insulation / building envelope seal or you have a leak. I really doubt the stove has anything to do with the mold. I'd look at the indoor humidity first. What's the RH of your interior and do you have a dehumidifier?

 

[jatoxico]

Where are you storing your wood? Fully dried wood (split and stacked >2 yrs) is OK but unseasoned or semi-seasoned wood contains huge amounts or water.

 

[maple1]

Is this something common from introducing an extra heating source into the home?

No, not at all.

Also sounds like you had a mold problem previous to the stove. Likely from poor ventilation leading to excessive humidity, with extra humidity coming from all the plants you have. And now likely, I'm guessing, also coming from wet or green wood now being stored in the house.

Those are pretty low house temps. Getting the temps up might increase stack effect that might in turn increase the air exchanging/ventilation. Sort of a band aid run-around on the real problem, but might help. You need to measure humidity, and get the bad air out. We know nothing about your house though, there could be all kinds of stuff going on.

 

[brad wilton]

Woodstove acually makes air dryer,so it's something else.me thinks jatoxico might have hit the nail on the head.

 

[saskwoodburner]

I'm thinking the moisture from the plants is a big part of the problem. As others have said, the wood heat will decrease moisture. As well, we used to keep the trailer a lot cooler with the oil furnace before we discovered wood stoves, and no mold problems to speak of either.

 

[begreen]

Poor insulation and cool walls will tend to sweat on the inside of the exterior wall in the wall cavity The mold may have been there for a while, inside the walls. What is showing on the surface indicated a possible large problem. It's possible it has been growing for years in the walls.

You need to get this taken care of. Mold can cause serious long term respiratory disease. Open up the areas in the worst locations and investigate. Wear a mask.

 

[elmoleaf]

Outside temp also likely dropped since you began using stove. The greater temp difference between inside and outside, the more likely water vapor will condense on/inside your walls. Wet material supports mold growth. Top wall typical location, likely from settled insulation or wood top plate thermal bridging= colder interior wall surface. Google "dewpoint". Bottom wall could be thermal bridging or water dripping down inside wall cavity. Symptom treatment = run a dehumidifier, especially more as outside temp drops. Cause treatment= less houseplants and better bathroom and kitchen exhaust to reduce indoor moisture.

Note that woodstoves do not really remove moisture. If your house is somewhat leaky, a lot of dry winter air is drawn in to replace what has gone up the flue during use of the stove. Warm air air actually holds more moisture than cool air. In my own case, i went from putting pots of water on the stove to increase indoor humidity last year to this year running a dehumidifier. The reason why? I tightened the entire house envelope to reduce air infiltration. The woodstove was unchanged.