If you have had carpet installed in your home for a while, or you just moved into a home with carpeted floors, you may have noticed dark lines around the baseboards. These lines can be particularly prominent on lighter-coloured carpets, and can also be sometimes found around the base of furniture or doorways.
These dark marks are called filtration lines, and they are caused by the airflow from your home’s HVAC system. Warm air carrying dust and pollutants from your duct work is attracted to cooler surfaces, which explains why filtration lines occur around your baseboards. The soils that form filtration lines are extremely small, oily, and carry an electric charge which bonds them to the fibers of your carpet. This is the reason why filtration lines can be nearly impossible to remove, unlike the normal soiling found on carpets.
Will Carpet Cleaning Remove Filtration Lines?
Unfortunately, a standard carpet cleaning process will not remove filtration soiling. The chemical composition of filtration soil along with their electrostatic charges make them next to impossible to remove in most instances. Additionally, the close proximity of filtration lines to the baseboard means that most cleaning methods would risk damaging the paint or scratching the baseboard wood.
Even when filtration lines can be successfully removed, they will tend to return after a few months. Houses located in cooler climates are more susceptible to filtration soiling, due to the larger variance between indoor and outdoor temperatures.
How To Deal With Filtration Lines?
Well-insulated houses are less likely to have filtration soiling, as insulation reduces the temperature variance throughout the home. Regularly changing your furnace air filter and having your ducts cleaned will reduce the amount of airborne pollutants which cause the soiling. One option for carpets with existing filtration lines is to strategically place furniture around the edges of your room in order to hide the dark lines. When installing new carpet or replacing your old carpet, look for darker colours which help to hide dark staining.