This species is a little larger and darker than the common furniture beetle. The females lay only about 10 eggs, usually in spring, in cracks and crevices in the timber. Development normally takes 2-3 years. When fully grown the larvae pupate and a couple of weeks later they metamorphose into adult beetles. This usually takes place during the autumn, but the beetles do not then emerge, but overwinter in the pupal chambers and gnaw their way out in the following spring.
This species attacks rotting branches or trunks of conifers, and when found in houses it is always in timber which has been softened by fungi. In some cases the infected timber is almost completely reduced to powder, with only the hard summer wood remaining in the form of thin lamellae.
An attack by this beetle will only be successful if the timber is damp, so the first step in controlling it is to find the source of the damp. Even when this problem has been solved the larvae may still go on developing in timber that has been damaged by damp, so any infected timber should be treated or even replaced. The beetles can- not live in healthy dry timber