Black marks on edge of carpet. Can they be re removed and how to prevent them coming back.

As seen in the picture opposite, black marks at the edge of the carpet have appeared. They have also appeared along the middle of the room. In this instance the black marking to the carpet is quite severe and had appeared over a period of time throughout this 1930s home.This was synthetic man made polypropylene carpet. Many polypropylene carpets can be quite stain resistant and in this instance the black marks were successfully removed. If these these carpets were made from wool they probably wouldn’t have come out.

Many types of polypropylene carpets can be highly stain resistant and the fibers cannot absorb staining. On the other hand, wool is a natural fiber and the staining can be irreversible as any black mark stains will be absorbed. So in many cases, black marks can be very difficult or impossible to remove from wool fibers.


how to remove black marks on edge of carpet

Whats causes blacks on the edge of carpets?

The black marks are caused by air moving around the gaps at the edge of the carpet. This air movement can often be evident across the middle of the room from gaps in the floor boards which can cause the same black marking.

The main cause is air pollution which circulates around the room. Homes which are near main roads and heavy traffic are more prone to the problem. Another cause is air from kitchen cooking that circulates around the home.

These Black marks on the edge of the carpet are often referred to as draught marks or filtration soiling.


draught marks information


cleaning black marks from edge of carpet

Can the black marks on the edge of the carpet be removed?

If the carpet is made from wool or a wool mixture, it can be very difficult and often impossible to remove these types of stains. If the carpet is made  from synthetic fibers, there is a good chance that they can be removed with stain removers. It is often better to call a professional carpet cleaning company to deal with these types of stains, as once the carpet is treated with stain removers, it will require cleaning out with professional equipment to extract both the dirt and the residue.

Can these stains be prevented?

There is no guarantee that this can be prevented. However,  lifting the carpet and sealing off any joints between the skirting and floor boards to reduce the air flow will in many cases stop the problem reoccurring.

If the black marks are occurring towards the middle of the room, the laying of wall lining paper between the underlay and the floor should prevent this. When using the paper, seal the overlap with adhesive tape.


A bad case of black marks appearing at the edge of the carpet. The black marking has also appeared along the middle of the room. These marks were successfully remove using a high alkaline professional cleaner and hot water extraction.

black lines at edge of carpet

In the same home the marks had appeared around the fireplace and were caused by the carpet fitting tool which had punched small holes in the carpet backing allowing the air to circulate.

filtration soiling on carpet

tips on removing carpet stains

General tips and advice about stain removal

Scrubbing and wetting:

Avoid over wetting a carpet. Over wetting can cause the cellulose from the backing to dissolve and permanently stain the carpet brown. Always try to use a suitable sprayer and lightly apply to dampen the carpet to allow the stain remover to work

Scrubbing can also damage the pile of the carpet. If you have had to scrub the carpet to dislodge any caked on dirt, carefully trim off any fluffed carpet pile when dry.

Always pre test stain removers in an inconspicuous area beforehand. Some types of stain removers can affect the colour or bleach the carpet.


Using dish washing liquid to remove stains from carpet.

It is often a mistake to use dish washing liquid or detergent to try and remove stains from a carpet. Used in a very small amount and diluted sufficiently, it probably won’t cause much of a problem. Another problem is soaking the carpet which can often damage a carpet.

The problem occurs because the dish washing liquid is very difficult to remove from the carpet afterwards. The residue from the liquid is sticky and this residue will attract more dirt when dry. The washing liquid will stay sticky when dry and continue to attract dirt when the carpet is used. This is often the reason why many stains come back afterwards and the area gradually turns into a stain again. The washing liquid will also stay in the backing of the carpet and slowly wicks back up the fibers and continues to attract dirt.

tea stain remover