Application of preventative chemicals is best done during the framing phase of construction when all wood is accessible to treatment. A broad array of remedial methods is available for treating drywood termite infestations. Whole-structure treatments include fumigation and heating to control all accessible and inaccessible colonies. Because of technical challenges, heat treatments usually are not applied to the entire building, but are limited to known areas of infestation, and along with excessive cold, are classified as compartmental treatments. Heat treatments are used to eradicate drywood termites from a portion of a house such as an attic, porch, or bedroom, or from an individual apartment or condominium unit inside a multi-family dwelling.
Hot air is delivered using high-output propane heaters.
Excessive cold is primarily used for treating wall voids or similar small enclosures in a structure. Liquid nitrogen is delivered into these voids until the temperature falls to a level lethal to drywood termites. This is the simplest and most direct method of treatment. Spray and foam applications of products containing boron salts are applied to raw, uncoated wood surfaces. Because penetration depths of borate solutions and depth of drywood termite galleries vary, drill injection into infested wood should also be performed.