There are 7 key things that home owners can do to help prevent infestations of wood destroying insects (WDI). The three most common types of WDIs are termites, carpenter ants, and carpenter bees.
WDI Infestation Prevention Tips -
1. Siding/grade contact - Ensure at least a 4” spacing between siding materials and grade. I often find siding terminating at or below grade and this makes insect entry more likely and harder for humans to detect visually. Termites and carpenter ants most often have ground nests and when siding contacts the ground directly, it provides a better avenue for directing them into the home. The two most common culprits are siding installed too close to the ground and having excessive amounts of mulch against the home. A proper empty buffer is needed between siding and grade.
2. Vegetation contact with the home or roof – Bushes and trees need to be trimmed back from the home to help prevent damage to siding and roof coverings but also, like with siding/grade contact, to prevent a direct connect between the home and grade. Carpenter ants especially can easily enter the home via bushes, overhead wires, and tree branches contacting the home well above grade. Keeping bushes trimmed back at least 24” and tree branches at least 5’ from siding and roof materials is recommended. Of course, since the vegetation will continue to grow, trimming needs to be done regularly.
3. Caulking – Ensure that all small openings and joints at the home’s exterior are kept well caulked. This includes around windows and doors, where different siding materials meet (such as masonry and vinyl), where cables/pipes enter the home above grade, and where any small cracks in the foundation exist. Also, don’t forget where the chimney meets the siding. These smalls cracks are inviting to WDIs. Using a good exterior-rated silicone caulking can help keep insects out as well as water and cold air.
4. Fix plumbing and roof leaks – Carpenter ants especially can easily find wet wood in the home such as from roof and plumbing leaks. Regular inspections under sinks, in the attic, and in the basement for water leakage and making prompt repairs, as needed, of the leak and any damaged materials, can help prevent the possibility of a wood destroying insect (WDI) finding the wet wood later on.
5. Keep firewood away from the home and garage – Storing firewood in the home, basement, or garage can bring wood destroying insects into the home since they may be nesting undetected in the wood. Keep firewood stored at least 10’ (20’ is better!) away from the home, elevated above the ground, and covered with a tarp will help prevent WDIs from getting to the wood plus it will keep the wood dry for better burning.
6. Regular inspections by a professional – Having a professional inspection performed regularly by a licensed exterminator can help prevent WDI infestations or may find them before the damage gets worse. Like most things around the home, preventive maintenance is key.
7. Nickel or quarter sized holes in exposed wood trim or siding - Carpenter bees love to bore holes. Look for almost perfectly round nickel or quarter-sized holes in exposed wood trim at the home's exterior. This could include wood siding, soffit and fascia boards, or other areas of wood trim. Their droppings are often visible near or below these holes. Like carpenter ants, carpenter bees are nesting in the wood and not consuming it. Once carpenter bees bore into the wood, they typically continue either to the right or left and then lay their eggs.
Most wood destroying insects are normally active in the April to October period in our area (south central PA). They are most often dormant in the winter months, although warmer weather late in the fall or early in the spring can skew this dormancy period.
Even though the detection of wood destroying insects (WDI) is outside the scope of a home inspection, home inspectors should report on issues 1-5, and 7 noted above to help minimize potential insect infestation and damage. Additional information about WDI inspections can be found here: https://elizabethtown.wini.com/services/wdi-inspection/
We use the standard NPMA-33 form (updated July 2019) for our WDI/Termite Inspections which are used/accepted by all lenders.
You can find our full service list under the Services tab at the top of our website: https://elizabethtown.wini.com
© 2014 Matthew Steger
Matthew Steger, owner/inspector of WIN Home Inspection, is a Certified Level 1 Infrared Thermographer, an ASHI Certified Inspector (ACI), and an electrical engineer. He is also licensed by the PA Dept. of Agriculture as a pesticide applicator/WDI inspector. He can be reached at: 717-361-9467 or firstname.lastname@example.org.
WIN Home Inspection has provided a wide array of home inspection services in the Lancaster, PA area since 2002. This article was authored by Matthew Steger, ACI - owner of WIN Home Inspection in Lancaster, PA. No article, or portion thereof, may be reproduced or copied without prior written consent of Matthew Steger.