You've found a house in Westchester. You've scheduled the home inspection. You feel covered. But unless someone specifically arranged a WDI inspection — wood-destroying insect inspection — there's an entire category of costly structural damage that your home inspector isn't looking for and isn't qualified to assess.
This isn't a criticism of home inspectors. It's just a scope issue. General home inspection and WDI inspection are different disciplines with different licensing requirements in New York State. Your home inspector looks at systems: HVAC, plumbing, electrical, structure. A WDI inspection, performed by a licensed pest management professional using the NPMA-33 form, looks specifically for evidence of termites, carpenter ants, wood-boring beetles, and similar insects that destroy structural wood. One inspection does not substitute for the other.
In Westchester County — where older wood-frame housing is common, where subterranean termites are a documented presence, and where carpenter ant activity is nearly endemic in aging structures — skipping the WDI inspection is a real financial risk. The good news is that it costs $150 to $250 and takes a couple of hours. The alternative is discovering an active termite colony after you've taken title, which costs orders of magnitude more and gives you no recourse against the seller.
Buying a home in Westchester? Call (877) 938-6799 to connect with a licensed WDI inspection provider.
Home Buyer's Pest Inspection Timeline
Timeline is illustrative. Your contract terms and contingency windows govern actual scheduling requirements. Consult your attorney and real estate agent.
What the WDI Inspection Actually Covers
The standard NPMA-33 form used for WDI inspections in New York documents four categories of wood-destroying organisms: subterranean termites, other termites (including drywood termites, though rare in Westchester), carpenter ants, and wood-boring beetles such as old house borers and powder post beetles.
For each category, the inspector records whether there's visual evidence of active infestation, evidence of past infestation with damage present, or conditions considered conducive — things like wood-to-soil contact at the foundation, moisture-damaged sill plates, insufficient crawl space ventilation, or wood debris in the substructure. Conducive conditions matter even if no active insects are found, because they indicate elevated risk going forward.
What the WDI inspection does not cover: moisture testing, mold assessment, general structural evaluation, or any pest category outside wood-destroying insects. It won't catch a mouse problem or a cockroach infestation. Those require separate assessment. For a broader pre-purchase perspective, see our pre-sale pest inspection checklist — it covers what sellers typically know going in.
When to Schedule It in the Transaction
Book the WDI inspection during the same window as your general home inspection — ideally within a few days of your offer being accepted. Your contract contingency periods are the window during which you can negotiate based on inspection findings or walk away without penalty. If you schedule the WDI inspection too late, you may have already passed the contingency deadline before you have the results.
The inspection needs to happen before your final walkthrough. The final walkthrough is not the time to discover a problem — it's a verification step, not an evaluation step. Have all your inspections done, results reviewed, and any negotiations complete well before you're standing at the front door with a set of keys in your hand.
Some buyers ask whether they can just rely on the seller's disclosure. Seller disclosure in New York requires sellers to identify known material defects. But a seller can only disclose what they know — and termite activity hidden in a basement wall isn't something most sellers are aware of. Disclosure is not a substitute for inspection.
What Happens If Active Activity Is Found
Finding active infestation during the inspection contingency period is actually the best possible outcome. You have information. You have options.
You can ask the seller to arrange and pay for professional treatment before closing. You can request a price reduction proportional to treatment costs. You can add a treatment contingency requiring documented treatment and a clean follow-up inspection before you proceed. Or, if the infestation is severe and the seller won't negotiate, you can use the contingency to exit the contract and retain your deposit.
What you cannot do — once you've taken title — is go back to the seller with a pest problem. Closing transfers the risk. From that point forward, what's in the walls is your problem and your cost. A termite treatment for a Westchester single-family home runs $1,200 to $3,000 or more depending on construction type and colony size. Structural repairs come on top of that. Against that exposure, the $150–$250 cost of a pre-closing WDI inspection is trivial.
For more on what the NPMA-33 form covers and how to read it as a buyer, see our guide on what to expect from a WDI inspection and the related explainer on WDI reports for Westchester realtors and buyers.
Getting a WDI Inspection in Westchester
A WDI inspection must be performed by a licensed pest management professional. In New York, that means a licensed pesticide applicator. Your general home inspector, unless they hold a separate pest management license, is not qualified to perform or sign off on an NPMA-33 form.
You can arrange a WDI inspection independently — you don't need to use whoever the seller's agent suggests. Getting your own inspector means the professional's obligation runs to you, not to facilitating the sale. Our new home pest inspection page connects you with licensed providers who serve Westchester County. Pricing context is in our Westchester pest control cost guide.
Frequently Asked Questions
Is a WDI inspection required to buy a home in New York?
Not legally required for most conventional purchases, but often required by FHA and VA lenders. More importantly, it's the only way to get documented information on wood-destroying insect activity before you take title. The general home inspection doesn't cover this. In Westchester County's older housing stock, skipping it is a meaningful financial risk.
What's the difference between a home inspection and a WDI inspection?
A general home inspection covers structural, mechanical, electrical, and plumbing systems. A WDI inspection (NPMA-33 form) is performed by a licensed pest management professional and covers termites, carpenter ants, and wood-boring beetles specifically. They have different scopes, different training, and different New York licensing requirements. You need both.
What does a WDI inspection actually cover?
The NPMA-33 form covers subterranean termites, other termites, carpenter ants, and wood-boring beetles. The inspector documents active infestation, past infestation with damage, and conducive conditions. It does not cover moisture testing, mold, general structural damage, or pests other than wood-destroying insects.
What happens if active termite or carpenter ant activity is found before closing?
Finding it before closing is the best possible outcome — you have options. You can negotiate for the seller to treat before closing, request a price reduction, add a treatment contingency, or walk away with your deposit. Finding it after closing means the cost is entirely yours with no recourse against the seller. That's why the pre-closing WDI inspection matters so much.
How much does a WDI inspection cost in Westchester County?
Typically $150 to $250 for a standalone WDI inspection. Some providers bundle it with a general pest inspection. The cost is a small fraction of what active termite or carpenter ant damage costs to remediate — or what you'd pay after closing without any recourse against the seller.