We all have the nasty grey and black edges around our carpets. It builds up eventually around all homes. It’s known as filtration soiling.   It’s due to poor circulation in the air filters.  Filtration soiling occurs as a result of air being forced into the room or space at a higher rate than it can escape from the same area, via the ventilation system.  As the air is forced through these gaps, it passes through the carpets and doors which acts as a filter to the air. When your heating/air conditioning unit is turned on, it builds up pressure and this is where it escapes. The soot and very fine microscopic particulates that are floating in the air get trapped here in the carpet along the edges. Your carpet acts as a filter to the air passing through the face fibers of the carpet. Notice that the dark lines are more prominent along the perimeter of the house

Any pollutants in the air are trapped by the carpet, and turn the carpet gray or black in that area. It’s difficult for your vacuum cleaner to reach every single spot on your carpet, over time the ultra-fine particles have a chance to really bond with the carpet and become more apparent. Especially in those areas that are harder for your vacuum to reach — like around the baseboards!

Helpful tips:

  • For the best results contact your local carpet cleaning company the cleaning method that is likely to be most successful is hot water extraction.  Carpet cleaners use solutions that will remove the harsh lines.
  • Change your HVAC (furnace/air conditioner) filter on a regular basis 1-3 months depending on your household.  More active household with kids and pets changing your filters once a month for best results.
  • Have Your Heating/Cooling System Inspected on a regular basis.  Your system should have designed air returns for good circulation.
  • Look for spaces between the wall and floor.  Seal the cracks with a good quality caulking.

We all live with this constant problem.  No matter how much we vacuum our floors we cannot keep the grey and dark lines off our carpet edges unless our filtration system is in check.