Adult clothes moth do not damage clothing. Their function is purely to reproduce. They lay eggs in fabrics, which develop into larvae.
The larvae can cause great damage to carpets and clothing by eating the fibres. The most common site for this damage is in dark corners or under furniture where there is little disturbance. An infestation is not usually detected until after vacuuming and a section of carpet is found to be bare, or a piece of clothing is taken out of a cupboard and holes are found.
After inspection it is usually possible to find small larval cases in the vicinity of this damage. These cases are light in colour and 7mm to 9mm long. They are made of silk and can be quite difficult to dislodge.
It is not uncommon for larval cases to be found on the wall and ceiling, making treatment quite extensive. The eggs will lay dormant in the carpet of fabric for many weeks and any chemicals used must have a long residual active life.
As well as carpets and clothing, These insects will eat upholstered furniture, animal furs and fur coats, Baize and felt, wool etc.
Infested material must be located and treated. The whole property will also need to be treated in order to control the infestation.