This condition is known as “soil filtration” or “carbon filtration”. Your home is under pressure, both positive and negative. As your furnace or air conditioning units run or cycle, they push (positive) or pull (negative), air pressure. This forced heating or cooling will cause soil filtration in any gaps in your structure, I.E. along walls, under doors, and especially stairways and closets. This problem is slow, but is constantly at work. Some tips for dealing with filtration soil are:
- Change your furnace filter monthly
- Have your furnace and duct work cleaned periodically
- Vacuum edges with a crevice tool
- Have a heating and cooling expert check your system for proper balance
Duo-Care can use a variety of cleaning agents on this problem to help reduce the severity and improve the appearance greatly.