Woodlice are more a nuisance than a health hazard surviving in humid conditions and usually indicate your home has a damp problem.
Woodlice favour damp conditions and feed off decaying vegetable matter, dead insects, fungi etc. They do not cause structural damage. The infestation always originates from outside as they wander in usually at night, they are excellent climbers & will often come into houses from the chimney or through cavity walls.
An infestation of woodlice is usually a sign that your home has damp and decaying wood for them to thrive. If this happens in your property then it means it’s time to call pest control professionals immediately.