Woodlice

Woodlice have no teeth.

They can exist in cavity walls if there is any suitable material - birds nests, wood, which will most likely be damp enough at its surface to sustain them. Then they can make their way inside - such as around or through the ends of your joists :-)

They can exist in kitchens & bathrooms, or underfloors where a chimney vents to the under floor and lets moisture in (often directly if a pepperpot chimney cap).

If you are finding dead woodlice, they are coming in from somewhere - which may well be outside - and then finding no food source inside.

I shouldn't worry too much. They will do no harm to you or your property. Unsightly perhaps but so are many other creatures that you really don't want to live with. This has been a wet and warm season, perfect conditions for woodlice. When my oldest son was a toddler, 30 yrs ago, he played with a wood louse and named it Eric. Since then all have been treated with respect and named Eric. None of the family have ever known anybody named Eric. Odd things children.

You shouldn't be looking for 'where they are coming from', this is an irrelevance, you should be looking for what is attracting them?

Where are you seeing them most?

if it's the kitchen or bathroom, you probably have an unnoticed leak - woodlice can't live without moisture, so they've done you a favour here by pointing out that you have a damp problem somewhere along the line, cure this and the chiggy-pigs will disappear.

Don't talk about Eric like that :-)

Got any bark mulch in the garden? Start nearest where they are in the house and work away. They'll be in dead plants or rotting wood. Even under leaves. A tidy up will fnd them.