You signed a contract on a home in Bucks County or Montgomery County, the lender’s pre-approval letter is in hand, and the settlement coordinator just sent over a closing checklist that includes the line “WDI report required.” Most buyers have never seen the term before. It is short for Wood Destroying Insect, and the report is a one-page form your loan file cannot close without.
This article walks through what a WDI inspection is, why your lender wants one, what the inspector actually looks for, what happens when something turns up on the form, and how to coordinate the visit so it does not slow your closing date.
What Is A WDI Inspection And What Does It Cover?
A WDI inspection is a focused exterior and interior evaluation of a home for evidence of wood destroying insects and the conditions that invite them. The licensed inspector documents findings on a National Pest Management Association form called the NPMA-33, which is the report your lender, your title agent, and the closing attorney all recognize by name.
The form covers four pest categories: subterranean termites, carpenter ants, powderpost beetles, and carpenter bees. It also notes prior treatment evidence such as drilled foundation holes or treatment stickers, and it documents conducive conditions that make a home easier for pests to enter. That last category is broader than buyers expect and includes wood siding touching soil, mulch beds piled against the foundation, leaky downspouts, and crawl space moisture.
It is worth separating this from a general termite inspection. A termite-only check looks for one pest. A WDI report looks at the whole wood destroying insect group plus the structural conditions around them. Subterranean termite damage is the most common finding lenders see in southeastern Pennsylvania, and the damage pattern is what trains a WDI inspector’s eye for the rest of the form. That broader scope is exactly why lenders rely on the WDI version rather than a generic pest letter.
Which Loan Types Require A WDI Report?
Not every mortgage requires a WDI report. Whether you need one depends almost entirely on the loan product your lender is underwriting.
VA Loans
VA-backed loans require a WDI report in Pennsylvania because the state sits inside the VA’s designated termite probability zone. The seller usually pays for this inspection on VA purchases because VA charge rules limit certain buyer-paid items. Your real estate agent and lender confirm the cost split before the order goes in.
FHA Loans
FHA loans require a WDI report when the appraiser sees evidence of past infestation, soft sills, or wood-to-soil contact during the appraisal. In Bucks and Montgomery County, where many homes have wood siding close to mulch beds or a partial basement with exposed sill plates, an FHA appraiser often flags this and triggers the WDI requirement.
USDA Rural Development Loans
USDA Rural Development loans on eligible parcels in upper Bucks and northern Montgomery County follow a similar rule and require a current WDI report before underwriting clears.
Conventional Loans
Conventional loans usually do not require a WDI report unless the appraiser specifically calls it out. The buyer can still request one for peace of mind, and many do, especially on older Philadelphia row homes and pre-1960 single family homes where powderpost beetle and carpenter ant activity is more common.
Whatever your loan type, the report has to arrive before closing. The most common scheduling mistake is treating the WDI as a separate item to handle later, then running out of time inside the inspection contingency window and rushing the lender during the final week. Schedule the WDI on the same day as your home inspection whenever possible.
What Does A WDI Inspector Actually Check?
The WDI walk is a visual, accessible-area inspection. The licensed pest control operator does not open walls, pull insulation, or move stored boxes. The inspector walks the home and the lot, looks at the four pest categories on the NPMA-33, and notes what is visible and accessible.
Outside The Home
On the outside the inspector looks at the foundation perimeter for mud tubes, which are the pencil-thick brown tunnels subterranean termites build between the soil and the wood above. The inspector checks exterior wood trim, porch posts, deck framing, and any wood that touches or sits close to the ground. Carpenter ant frass (sawdust-like debris) under wood door frames, in the garage, or near tree stumps is another visible flag. Carpenter bee exit holes in fascia boards and porch beams are also documented.
Inside The Home
On the inside the inspector heads to the basement and crawl space, where the sill plate (the horizontal wood sitting on top of the concrete foundation) is the most common entry point for subterranean termites. The inspector probes accessible sill plates and floor joists for hollow-sounding wood or soft spots, looks for mud tubes climbing the foundation wall, and notes any signs of prior treatment such as drill holes in the foundation. Powderpost beetle exit holes in older floor joists, attic rafters, and antique wood trim get documented too.
These findings overlap with the broader list of items that turn up on Pennsylvania inspection reports, and a good inspector cross-checks both. Conducive conditions are noted even when there is no active pest, because the next buyer or the next lender on this property will see them on the same form.
What Happens If The Report Finds Active Infestation?
The WDI form has three result categories. The cleanest is “no visible evidence of active infestation.” The next is “evidence of previous infestation, no active infestation.” The third is “active infestation observed.” Each one points to a different next step.
No Visible Evidence
This is the result most buyers want. It clears the lender condition and the file moves toward closing without further action.
Previous, Not Active
This usually does not block closing on its own. It tells the lender there was past damage, often already treated, and that the home is currently clear. The buyer may still want a structural review of the area where the prior damage occurred to confirm the damaged wood has been repaired or assessed by a contractor. This is where buyers sometimes ask for a written letter from the seller’s treatment company confirming the warranty is transferable.
Active Infestation Observed
An active termite infestation does not automatically kill the deal. It shifts the conversation to treatment. The seller commonly pays a licensed pest control operator to treat the home, provides a written treatment record, and the WDI inspector returns for a re-inspection. After the re-inspection a clean report is issued and sent to the lender. In most Bucks and Montgomery transactions this happens inside the inspection contingency window without delaying closing.
What buyers should not do is ignore an active finding because the seller volunteers to treat. The treatment paperwork and the re-inspection have to land in writing in the lender’s file, otherwise the underwriter holds the file at the last hour and closing slips by days or weeks.
How Does A WDI Inspection Fit With Your Home Inspection?
A home inspection and a WDI report are two different scopes performed under two different licensures. Your general home inspector is licensed under the Pennsylvania Home Inspection Law. Your WDI inspector is licensed as a pest control operator through the Pennsylvania Department of Agriculture. The two licenses do not overlap by default, although some inspectors hold both.
Looking at the full scope of a home inspection against the WDI scope is the easiest way to see the difference. The home inspection covers the major systems including roof, structure, electrical, plumbing, HVAC, and exterior. The WDI walk narrows in on wood destroying insects and the conditions that invite them. Most home inspectors recommend running the two together so the buyer sees the full picture in one report set rather than across two separate visits.
When the two are scheduled together, the WDI inspector typically arrives at the same time as the home inspector, performs the WDI walk during the same visit, and issues the NPMA-33 form within 24 to 48 hours. The buyer pays for both at the time of inspection in most transactions, and the title company collects the invoice copies before clearing the file.
If the home inspector finds conditions that overlap the WDI scope, such as a damp crawl space or wood-to-soil contact along the back porch, both reports will note the issue. That is not a contradiction. It is a useful cross-check, because the buyer can present two independent observations to the seller during the repair conversation rather than relying on a single inspector’s opinion.
Frequently Asked Questions About WDI Inspections
What does WDI stand for?
WDI stands for Wood Destroying Insect. A WDI inspection is a focused evaluation of a home for signs of insects that damage wood, most often subterranean termites, carpenter ants, powderpost beetles, and carpenter bees. The inspector writes the findings on an NPMA-33 form, which is the standard report lenders and pest control offices recognize.
Is a WDI inspection the same as a termite inspection?
It is the broader version. A termite inspection looks for one pest. A WDI report covers the full group of wood destroying insects plus, on most forms, evidence of past treatment and conducive conditions like wood-to-soil contact. Lenders almost always ask for the WDI report by name, not a plain termite report.
Who pays for the WDI report in Pennsylvania?
Custom varies by transaction. In Bucks and Montgomery County the buyer commonly pays at the time of their home inspection. On some VA purchases the cost is shifted to the seller because VA rules limit certain buyer charges. The settlement coordinator or real estate agent confirms who pays before the inspection is ordered.
How long is a WDI report valid?
Most lenders accept a WDI report dated within 90 days of closing. If your closing is delayed past that window, the lender can ask for an updated report. Plan the inspection so the report stays inside the 90-day window from the expected closing date.
Can the same person do my home inspection and my WDI inspection?
Only if that inspector also holds the Pennsylvania pesticide applicator license required to perform WDI inspections. Many home inspection companies coordinate the WDI report with a licensed pest control operator so both visits happen on the same day. Ask before booking so you do not end up with two separate trips.
Does an active infestation kill the deal?
Not by itself. An active finding shifts the conversation to treatment, repair, and re-inspection. The seller usually pays for a licensed treatment and provides documentation, then the WDI inspector returns to confirm the treatment is complete before the lender clears the file. Most loans close on time when the finding is addressed inside the contingency window.
How Should You Plan Your WDI Report Around Closing?
The WDI report is a small line item that becomes a closing emergency only when it gets scheduled too late. Order it with your home inspection, confirm the inspector is a licensed Pennsylvania pest control operator, and plan the closing date so the report stays inside the 90-day window the lender accepts. If the report flags an active finding, give the seller and the treatment company enough time to treat, document, and re-inspect before the contingency window closes.
If you are buying a home in Bucks County, Montgomery County, or Philadelphia and need a WDI report coordinated alongside your home inspection, schedule your inspection with our team so the visit is set up correctly the first time.