Published on February 4th, 2018 | by Henri0
Black soot above baseboards
Q. I hope you can help me with a problem I have with black soot above my baseboards. Our furnace has been inspected, cleaned and I have been assured that the furnace is not the issue. However, I have black soot in every room above my baseboards.
The baseboards are clean and they don’t blow the heat anyway. This is soot because it just swirls when I try to clean it. We have painted rooms because of this but within 6 to 9 months we start seeing it again. Please help.
A. This is a common problem. It may be caused by the use of many candles, smokers in the house, exterior walls that get cooler when the baseboards are not generating heat, or other pollutants in the air that are drawn into the baseboards from the floor when warm air is rising from them.
If the exterior walls are only built with 2×4 studs and are insulated with 4-inch fiberglass or cellulose, they are not up to today’s standards and can be cool enough in cold weather to allow light condensation on the interior finish. This can be aggravated if the insulation was not very carefully installed and there are empty spaces around the walls’ bottom plates.
Invisible condensation can form on the inside finish of the exterior walls, particularly near the bottom of the walls, which are colder. The warm air rising from the radiators, carrying any pollutants from the sources mentioned above, particularly if the floor are carpeted, deposits these pollutants on the misty walls as downdrafts descend along these walls.
If the soot, or whatever the composition of the stains is, is not thoroughly removed and the walls thoroughly cleaned, the stains will bleed through the paint over time.
If the cause of the problem is not removed, the stains will recur regardless of any cleaning efforts. Reducing or eliminating the source(s) of the pollutants and vacuuming the floors often may help, but the wall construction is harder to improve.by