Good regular vaccing is the secret, but you cant allways move that big heavy sofa or that cupboard in the corner.
I probably do 4 to 6 of these a year.
I use Stapro's product with permethryn in it. Allways works, only had 1 call back in 15 years or so and that was a grumpy farmer who asked what was in it, told him and he said he could have done it so I told him why didnt you. Didnt get called back.
It happens a lot around the coastal areas where the atmosphere is damp, doesnt mean house is dirty, they just happen. If you see a moth flying around and it turn into dust if you touch it, thats the one to watch out for.
If infestation is severe you are supposed to uplift carpets round the edges and vac between grippers and walls to get rid of the eggs, but that makes it very expensive.
Just spray product round the edge of the room, in cupboards etc, they are found around the edge of the room because as you walk through the room you crush the eggs, simple eh.
When the moth comes out of its shell it eats the carpet which is wool (not man made) and has been treated by you and dies, no more moth, no more problem.They do not have a specific breeding time ie summer autumn etc they just breed.
I did a normal clean in posh house once, saw the damage in the study and told her I could spray it there and then, she said Rentokil had done it a few months earlier asked how much just to get an idea and she said £400.00. Told her its only a sachet and how much I would have charged, the look on her face was a picture.
I usually price it with a clean to make it look better, go for it, its not rocket science, I usually carry a couple of sachets in the van, you never know when you will need it. But allways use PPE with it, just to be on the safe side.
Murky