Deathwatch beetle infests old oak timbers previously affected by fungal decay which means that removing, or preventing an infestation is to ensure timbers are dry. This issue commonly occurs at the ends of joists or rafters and signs that show you have an infestation include 2mm or 3mm holes in the timbers.
Damage is not actually caused by the adult beetles but rather their larvae inside the timber which can last for up to 13 years. Spraying insecticide to the surface can actually make matters worse as it only kills spiders and other insects which are the deathwatch beetle's predators.
At Pro Dry we recommend that the most effective treatment for deathwatch beetle infestations, which can be very serious, is to ensure that timbers are dry by fixing any sources of moisture and ventilation.
Are you worried about structural damage to your property? Get in touch with Pro Dry and we can send an experienced structural engineer to undertake an investigation and reveal any rot to internal areas.