Continuous Running Bath Fans
user-1045541
| Posted in Energy Efficiency and Durability on
We’ve noticed a black film on the vinyl siding around the exhaust vent of the continuous running bath fan on several houses we have built. It seems like the exhaust could be facilitating mold growth, or just causing the siding to be dirty. Has anyone else come across this? Does this mean the bath fan is just doing its job and cleaning the siding around the exhaust would be normal maintenace? Thanks
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Replies
Jason,
I can think of three possibilities:
1. The dark stain is an accumulation of particulates from indoors; this might happen if the owners smoke cigarettes, burn candles, or roast a lot of meat indoors.
2. The dark stain is an accumulation of particulates (dust, pollen, etc.) from outdoors that adhered to the damp spot that forms when humid bathroom air condenses on the siding.
3. The dark stain is mold that grows on particulates that adhere to the damp spot.
Solution: soap and water and a scrub brush.
Martin, thanks for your input.