NC Department of Agriculture WDIR
Structural Pest Control Section
A Homebuyer’s Guide for the
Wood-Destroying Insect Report (WDIR)
By law, an inspection for wood-destroying insects and their evidence is the careful visual examination of all accessible areas of a building and the sounding of accessible structural members adjacent to slab areas in contact with masonry walls and other areas particularly susceptible to attack by wood-destroying insects. Evidence includes both present and past activity of wood-destroying insects visible in, on or under a structure, or in or on debris under the structure. Permanently attached decks, porches, storage sheds, etc. are included in these inspections. Outbuildings or other detached structures are not routinely inspected unless specifically requested by the client. In order for the inspection to be completed correctly, the pest control operator (PCO) must have access to all interior and exterior areas of the structure to be inspected. Paragraphs I through 4 of the “Conditions Governing This Report” on the reverse side of the form, will discuss the extent of the inspection performed. Be familiar with these conditions. The PCO must indicate areas of the structure that were inaccessible at the time of his inspection. Obviously inaccessible areas, such as inside walls, beneath carpet or other floor coverings, etc., will not be listed separately. An inspection of inaccessible areas may necessitate the removal of walls and to provide access, which an additional fee may be charged.What will be reported?
The WDIR is issued for informational purposes and is required to reveal information concerning evidence of wood-destroying insects only. The PCO must report all visible evidence of wood-destroying insects and any conditions conducive to subterranean termites. The WDIR is not a warranty as to the absence of wood-destroying insects; it is a report of the visible presence or absence of wood-destroying insects at the time of the inspection.Though sometimes referred to as a clearance letter or a termite letter, it is not a “clearance letter,” in that it does not necessarily clear a structure; and it is not a “termite letter,” in that it addresses more than just termites. Insects commonly noted on the WDIR include subterranean termites, powder post beetles, old house borers, carpenter ants and sometimes carpenter bees. Other, less common insects may also be reported. “Conditions conducive to subterranean termites” must also be reported. At a minimum, wood making direct soil contacts, cellulose debris under a structure and excessively wet wood (wood moisture content of 20% or greater than) in the crawl space or other areas of the structure must be reported as conditions conducive to subterranean termites. The presence of wood-decay fungi may be listed as a condition conducive to subterranean termites. Other conditions that may be conducive to termites include insufficient clearance between wood members and the soil, excessive moisture in the crawl space, construction flaws or improper grading. The PCO must evaluate these and other conditions individually for each property inspected. Termites are very capable of finding the only possible entry point into a structure. They need only a 1/32 of an inch crack in a mortar joint or concrete expansion joint to enter a structure. They build earthen shelter tubes to reach the wood from the ground where they live. Termites can infest finished floors covered by vinyl flooring or carpeting, interior walls, and other areas that cannot be seen during a PCOs inspection. Furthermore, research has shown that termites can build tubes at the rate of approximately two and one-half inches per hour. Therefore, it is possible for termites to show up shortly after the structure has been inspected. This is also true when talking about old house borers. An inspection of the structure may not show evidence at the time of the inspection. However, depending on the age of structure they can become active after an inspection was performed.What conditions are not reported?
The PCO is not required to report the presence of damage or the extent of any damage. However, if the WDIR indicates that wood-destroying insects and their evidence are in the wooden members, it must be assumed there is some damage. The WDIR is not a structural damage report. Such evaluations should be left to a structural engineer, contractor or other building expert. The WDIR will not reveal the presence of or damage by wood-decay fungi (wood rot) or wildlife. Though the PCO may be the only individual who goes beneath or in the attic of the structure, he is not responsible for reporting everything that may be wrong with the structure. Structural and electrical defects and plumbing and roof leaks are not his area of expertise, except as the latter may cause conditions conducive to termites. Home inspectors or other contractors must be called to determine the integrity of these building elements. The PCO is not responsible for any evidence that may had been inaccessible at the time of the inspection. Buyers should take note of the areas listed on the form as inaccessible.
What happens if evidence of wood-destroying insects is found?
When a PCO finds evidence of wood-destroying insects (such as termite tubes or cast wings, damage or exit holes from wood-boring beetles etc.) he must report its presence and specific location on the WDIR. The report must clearly indicate whether or not the insects have been or are in the wooden members. If no evidence of treatment exists in the case of subterranean termites, the PCO may submit a bid to treat the structure. However, this is secondary to the object of the report, i.e., to report the infestation. His job is to tell you or your (his) client that the wood-destroying insect infestation is present. His obligation is then fulfilled. It is up to the seller or buyer to contract for a treatment if necessary. If a treatment is performed, a copy of the written agreement and warranty, if any, must be attached to the WDIR. Treatment options vary depending on the insect found the extent of the infestation, whether a previous treatment has been performed and whether or not a warranty is desired. Powder post beetle, old house borer and other wood-boring beetle infestations can be treated by an application of a liquid insecticide to the surface of infested timbers, by controlling excessive moisture in the timbers or by fumigating the entire structure (rarely recommended). Prior treatments for these insects are difficult or impossible to establish. Subterranean termites are typically dealt with by applications of liquid pesticides to the soil and voids in masonry foundations, denying the termites access to the structure, or by the installation of termite bait systems. A liquid treatment may be a complete treatment or a spot treatment. If a prior treatment has been performed or if a warranty is not desired, a spot treatment may be satisfactory. However, if the termite infestation is widespread or a warranty is required, a complete treatment of the structure is usually recommended. Termite baits have the advantage of requiring much less pesticide and work by eliminating or suppressing the termite colony itself. They may, however, take longer to control the infestation and require the payment of quarterly or annual fees to maintain the protection plan. The buyer and seller should discuss these options and agree on a treatment plan before the treatment is performed.What should be done if the wood-destroying insects have reached the wood?
If the WDIR indicates the wood-destroying insects are in the wooden members, it must be assumed there is some damage. Ordinarily, a PCO is neither prepared nor qualified to evaluate the extent of damage to a structure. A building expert should make the necessary repairs. The repair invoice may be attached to the WDIR. A PCO should not be expected or required to be a quality control inspector for carpenters, plumbers, etc. This is not his area of expertise or the purpose of the WDIR. Furthermore, the issuance of a subsequent report indicating “no evidence” in such circumstances would be a violation of the structural pest control rules and could be considered to be fraud. Most homes in North Carolina in excess of 10-15 years old will have some evidence of wood-destroying insects and could well have been damaged by such insects. Lending institutions and buyers need to realize that a “clear” report is not to be sought. The function of the WDIR is to report the presence of all visible evidence of wood-destroying insect infestation. If damage is present, it is the buyer’s responsibility to ensure that it is repaired or evaluated and acknowledged as of no structural consequence by a qualified contractor or engineer. Just as an individual is willing to buy a used car with a few dents; so a homeowner, lender, etc., must be willing to accept some wood-destroying insect damage in an older home.
The potential buyer depends on this report to help in the decision-making process on the real estate purchase and obviously would be quite upset if misled by an improperly completed report. A so-called “clear” report is not mandatory in order for the transaction to be completed. The most important thing to remember is that the report must be, as required by law, a true indication of the presence or absence of evidence of wood-destroying insects. The report should be obtained early in the transaction and be read carefully by all concerned parties, paying particular attention to the introductory statements on the report and conditions governing the report printed on the reverse.Questions concerning the WDIR in general or with regards to a specific inspection should be addressed to the Structural Pest Control Division of the North Carolina Department of Agriculture & Consumer Services.
Drywood termites house their colonies within the wood on which they feed. As they consume wood, they burrow mazes of tunnels and chambers within walls and furniture. Drywood termites leave small piles of feces that resemble pellets where they have eaten or nested. Drywood termites also cause sagging floors, walls, and ceilings and may leave behind areas which appear to be water damaged. After winged drywood termites swarm, their wings shed and can be found in small piles throughout an infested home. These wings resemble fish scales.
Drywood termites are usually found in warm, southern climates, while subterranean termites are found throughout the continental United States. Subterranean termites build their colonies underground and can travel above ground to access sources of food. They enter homes through cracked or unsealed foundations, as well as through tunnels constructed from mud, their feces and saliva. These tunnels are brown, dry and cylindrical in appearance. The presence of these tunnels near the foundation of your home is a sure sign of subterranean termite infestation. Just like drywood termites, subterranean termites produce winged swarmers which indicate an active termite colony.
Termites can cause severe damage to homes
Although termites are ecologically beneficial in that they break down detritus to add nutrients to soil, the same feeding behaviors that prove helpful to the ecosystem can cause severe damage to human homes. Because termites feed primarily on wood, they are capable of compromising the strength and safety of an infested structure. Termite damage can render structures unlivable until expensive repairs are conducted.
Structural property damage
Homes constructed primarily of wood are not the only structures threatened by termite activity. Homes made from other materials may also host termite infestations, as these insects are capable of traversing through plaster, metal siding and more. Termites then feed on cabinets, floors, ceilings and wooden furniture within these homes.
Because termites are often not identified before considerable damage has occurred, it is advised that homeowners experiencing a termite infestation contact a pest control professional before attempting to address the problem on their own. Professionals will conduct an inspection in order to correctly identify the problem and will then discuss possible avenues of treatment with homeowners.
Signs of subterranean termite damage
Subterranean termites dwell underground in loose, damp soil. Although subterranean termite species in Africa are famously aggressive and known for the obvious mounds above their colonies, signs of subterranean termite damage within the United States are much less obvious.
Interior damage may not become apparent until infestations are full-blown. Termite damage sometimes appears similar to water damage. Outward signs of termite damage include buckling wood, swollen and ceilings, areas that appear to be suffering from slight water damage and visible mazes within walls or furniture. Termite infestations also can exude a scent similar to mildew or mold.
Subterranean termites also access above-ground food sources through mud tunnels they create from saliva, mud and feces. These tunnels are located near the foundation of infested homes.
Signs of drywood termite damage
Drywood Termites build their colonies within wooden structures on which they feed. They can be found inside of walls or furniture. Drywood termite infestations may only become apparent after a colony has burrowed so deeply into an infested item that the veneer cracks and the maze-like tunnels beneath become visible. Such damage is common in antique furniture pieces. Should this occur on new furniture or the floors or walls of your home, contact a pest control professional to discuss the severity of your infestation, as well as extermination options.