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Re-roof and Retrofit WPI-8 Rules | Oasis Engineering Resources · 5 min read Re-roof and Retrofit WPI-8 Rules Most builders learn the WPI-8 process for new construction first — three to four inspections, drawings, full load path, the whole thing. Re-roofs, alterations, and retrofits work differently. The inspection scope is narrower, the form types are different, and the certificate covers only the work performed. Not all coastal Texas work needs a WPI-8 If the project is small enough or limited enough in scope, it may not require a WPI-8 inspection. The rule of thumb: if the work touches the structural system, the cladding system, or the openings — and the structure is in a designated catastrophe area — a TDI inspection process is generally required. Cosmetic work, interior remodels that don’t touch structure, and minor repairs typically don’t trigger the requirement. If you’re not sure, the safest move is to ask. The TDI windstorm program can confirm whether your specific scope requires a certificate. Common scopes and how the inspection process changes Re-roof (asphalt shingle, metal, tile) A re-roof is one of the most common WPI-8 inspection scopes. The TDI form uses an “Entire re-roof” or “Partial re-roof” classification. Inspectors verify decking attachment (especially if the deck is replaced), edge metal, drip edge, underlayment, and the manufacturer’s high-wind nailing pattern. The inspection typically requires one to two site visits — once after deck repair or replacement (if any), and once during or after the final shingle/panel installation but before any concealment. Re-decking only If the existing roof covering is being removed and the wood structural panels (deck) are being replaced or supplemented, the re-decking is a separate inspectable scope. Nailing pattern, edge attachment, and panel-to-panel gaps are checked. Window and door retrofit (opening protection) Retrofitting all exterior openings — windows, doors, garage doors, skylights — for windborne debris protection is its own WPI-8 scope. The TDI form has a specific checkbox for “Retrofit of all exterior openings.” This scope confirms that all openings carry product approvals and were installed per the manufacturer’s specifications. Important nuance: “all exterior openings” means all. A partial retrofit — replacing some windows but not others — does not qualify for the all-openings scope and may need a different documentation path. Addition An addition to an existing structure is treated as new construction for the addition itself. The addition needs its own load path, its own structural drawings, and its own inspection sequence (foundation, framing, final). The existing structure does not retroactively need to be inspected. Alteration (structural) Structural alterations — removing a load-bearing wall, adding a structural beam, modifying a roof system — require sealed drawings showing the modification and inspection of the altered work. The certificate covers only the altered scope. Repair Repairs to storm-damaged structures often need a WPI-8 process to restore insurability. Scope depends on what was damaged and what’s being repaired. Roof repair after a hurricane is one of the most common repair-scope inspection requests. Foundation only Foundation-only work — for example, repairing a damaged slab — has its own scope checkbox on the TDI form. Inspections focus on anchorage, embedment, and connection to the structure above. Mechanical only Rooftop equipment installation (HVAC condensers, exhaust units) on a coastal structure has its own attachment requirements and inspection scope. The structural attachment of the equipment to the roof is what’s inspected. The general principle: The WPI-8 covers the scope of work performed. A re-roof certificate covers the roof. A window retrofit certificate covers the openings. The certificate is not a blanket statement that the entire structure complies — only the inspected scope. What’s required regardless of scope Every scope — full new construction, re-roof, retrofit, repair — requires the same basic ingredients: WPI-1 application filed with TDI before the work is concealed Sealed drawings or scope documentation, prepared by a Texas-licensed engineer Inspection by a TDI Appointed Qualified Inspector during the work WPI-2-BC-8 reports for the inspections WPI-2E final affidavit submitted to TDI TDI review and issuance of the WPI-8 certificate The volume of work changes by scope, but the form structure is consistent. Pricing for re-roof and retrofit scopes Smaller scopes typically cost less than full new construction inspection. A re-roof inspection on a residential structure may run significantly less than the $3,000 standard residential inspection package, depending on access, schedule, and how many inspections the work requires. For specific quotes on re-roof, retrofit, or repair scopes, request a custom quote. Re-roof, retrofit, or alteration in the catastrophe area? Smaller scopes often qualify for shorter inspection sequences and lower fees. Request a custom quote and we’ll scope the right inspection path for your specific project. Request a quote → Related guides What is the WPI-8 Certificate?Plain-English overview of the certificate. TDI forms explainedWPI-1, WPI-2-BC-8, WPI-2E, WPI-8. Common deficienciesWhat inspectors flag during construction. Building without WPI-8The downstream consequences of skipping inspection.

What Happens If You Build Without a WPI-8? | Oasis Engineering Resources · 6 min read What Happens If You Build Without a WPI-8? It’s a question that usually gets asked too late: a coastal Texas property is built, the punch list is done, the owner is ready to close — and someone realizes there is no WPI-8 certificate. Here’s what actually goes wrong, and what your options are when it does. Three things break when there’s no WPI-8 1. The property cannot get windstorm insurance through TWIA The Texas Windstorm Insurance Association — TWIA — is the wind insurance backstop for the coastal catastrophe area. TWIA requires a WPI-8 to issue a policy on a structure built after January 1, 1988 in a designated catastrophe area. No certificate, no policy. 2. Most lenders won’t fund the loan Lenders require windstorm coverage on coastal properties before closing. If TWIA can’t issue a policy without the WPI-8, and private wind carriers are hard to find on coastal property, the loan can’t fund. The closing falls through or is indefinitely delayed. 3. Resale and refinance get harder Even years later, when the owner wants to sell or refinance, the missing WPI-8 follows the property. The next buyer’s lender will ask the same questions. The next insurance underwriter will too. Why this happens more often than it should The most common reason a project ends up without a WPI-8 is not malice. It’s that nobody on the project team treated the certificate as required infrastructure from day one. The architect drew the building. The contractor built the building. Inspections happened — but city or county inspections, not TDI windstorm inspections, which are a separate and parallel process. Then closing approaches, the title company asks for the certificate, and the owner finds out for the first time that the inspections needed to happen during construction — when the work was visible — and they no longer are. Can you get a WPI-8 after construction is finished? Sometimes. But it’s harder, slower, and more expensive than doing it right during construction. There are a few possible paths: Post-construction evaluation A Texas-licensed engineer can perform a post-construction evaluation of the existing structure. This involves visual inspection, partial removal of finishes (drywall, soffits, panels) to expose concealed connections, photographic documentation, and an engineering report on whether the existing construction appears to comply with the applicable wind code. This is more invasive than during-construction inspection because the work is no longer visible. The engineer cannot certify what they cannot see — so anything concealed has to be exposed enough to be evaluated. Sample inspection or destructive testing For larger structures, sample inspections may be acceptable. The engineer opens up representative areas — a few wall cavities, a section of soffit, a section of roof deck — and infers compliance for the rest from the sample. This is judgment-heavy and not always sufficient for TDI’s requirements. Re-roof or re-cladding the structure In some cases the simplest path is to redo the parts of the structure that need to be inspected. Re-shingling the roof gives an inspector a chance to see the deck nailing pattern, drip edge, and edge attachments. Re-cladding gives an inspector access to wall sheathing nailing. None of these post-construction paths are guaranteed. TDI may still find the file insufficient and decline to issue the certificate. The entire purpose of the during-construction inspection process is to avoid this scenario. What it costs when it goes wrong A standard during-construction WPI-8 inspection runs about $3,000 for a typical residential structure. A post-construction evaluation on the same property — with exploratory openings, photographic documentation, and a written engineering report — typically runs several times that, depending on how much exposure work is needed and how many of the connections can be verified visually. Add to that: the cost of patching what was opened up, the cost of project delay while the evaluation is performed, and the cost of carrying the loan and the property during the delay. How to avoid this entirely The fix is straightforward: file the WPI-1 application before construction starts, hire a TDI Appointed Qualified Inspector before the foundation is poured, and schedule the three or four inspections at the right milestones. The cost is predictable and the risk is contained. If you’re reading this because you’re already in the post-construction problem — the structure exists and the certificate doesn’t — the right next step is a conversation with an engineer who has handled post-construction evaluations. Some are recoverable. Some require redoing parts of the structure. The honest answer depends on the specifics of the project. Don’t end up here. Start with a clean inspection path. Oasis Engineering files the WPI-1, runs the inspections, and submits the WPI-2E so TDI can issue your certificate. Pay deposit online and lock in your inspector before the foundation goes in. View pricing & buy → Related guides What is the WPI-8 Certificate?Plain-English overview of the certificate. TDI forms explainedWPI-1, WPI-2-BC-8, WPI-2E, WPI-8. Common deficienciesWhat inspectors flag during construction. Re-roof and retrofit rulesInspection requirements for non-new-construction.

Common WPI-8 Deficiencies and How to Avoid Them | Oasis Engineering Resources · 7 min read Common WPI-8 Deficiencies (and How to Avoid Them) Deficiencies are the single biggest source of WPI-8 delay. Most are predictable and fixable — but only if you know what inspectors flag and when they flag it. Here are the items that come up most often on coastal Texas projects. Why deficiencies matter Each deficiency requires a correction and a re-inspection before the file can be closed out. Re-inspections cost time, cost money (typically $550 per visit), and can stall closing if they pile up at the end of the project. The good news: nearly every common deficiency is preventable with one practice — make sure the field crew can read the sealed drawings and is following them. The deficiencies below are not exotic. They are the same ones that come up over and over. Connection deficiencies 1. Missing or wrong-size hurricane straps and clips The drawings call for a Simpson H2.5 or H10A at every truss-to-top-plate connection. The crew installs them at every other one, or substitutes a smaller clip than what was specified. This is the most common single deficiency. How to avoid it Walk the framer through the connection schedule before framing starts. Keep the manufacturer-specified clips on the jobsite — substitutions are not free passes. 2. Insufficient anchor bolts at the sill plate Code requires anchor bolts at specific spacing and embedment depth. Common errors include skipping bolts at corners, using wedge anchors where epoxy was specified, or not achieving full embedment because the slab was poured short. How to avoid it Verify anchor layout before slab pour, not after. After the pour, a missing bolt is an epoxy retrofit — not impossible, but expensive and inspectable. 3. Missing nailing schedule compliance Wood structural panels (sheathing) require specific nail size, spacing at edges, spacing at field, and edge distance. Inspectors check for over-driven nails, missed nails, wrong nail size, and incorrect spacing — especially at panel edges and the corner zones where wind loads concentrate. How to avoid it Set the nail gun depth correctly and don’t rely on the framer to “eyeball” 6-inch edge spacing. Mark the panels. Uplift and load path deficiencies 4. Broken load path from roof to foundation Wind uplift travels from the roof down through the wall framing into the foundation. Every connection in that path has to transfer the load. Common breaks: missing strap from rafter to top plate, missing strap from top plate to stud, or a stud-to-sill connection that relies on toe-nails alone. How to avoid it Treat the load path as a continuous chain. Every link has to be there. The drawings show every connection — don’t skip any. 5. Header and beam connections under-specified Door and window headers — especially garage door headers — are concentration points for uplift and lateral load. Common issues: missing jack studs, missing header straps, or a header-to-king-stud connection that doesn’t match the schedule. How to avoid it Garage door openings are inspector hot spots in coastal Texas. Get those connections right the first time. Opening protection deficiencies 6. Windows and doors without product approval If the design wind speed is 140 mph or higher, code requires opening protection — either impact-rated glazing or shutters. Each product needs a Florida or Texas product approval (NOA) demonstrating compliance. A common issue is product mix-up: the architect specified one model and the contractor installed a similar but uncertified one. How to avoid it Keep product approval documents on file from the moment the order goes in. The inspector will ask for them. 7. Garage doors without windstorm rating Standard garage doors fail in hurricanes. Code requires reinforced or rated garage doors in the catastrophe area, especially for 140+ mph design wind speeds. Installing a stock door is an automatic deficiency. How to avoid it Order a windstorm-rated garage door from the start. Retrofitting after the slab and framing are done is much harder than ordering the right one upfront. Cladding and roofing deficiencies 8. Roofing nails too short or wrong pattern Asphalt shingles and metal roofing both have specific fastening requirements. Short nails that don’t penetrate the deck the required amount are a common finding — as are missed nail patterns at hip and ridge. How to avoid it Use the manufacturer’s high-wind nailing pattern, not the standard one. Coastal Texas is a high-wind zone by definition. 9. Soffit and fascia attachment Wind doesn’t just push on walls and roofs — it pulls under eaves and rips off soffits. A loose soffit becomes a path for wind into the attic, and once wind is in the attic, it lifts the roof from inside. Inspectors check soffit attachment, fascia connections, and vent details. How to avoid it Don’t treat the soffit like a finish detail. It’s a structural component in a hurricane. 10. Metal building cladding fasteners On metal buildings, the fastener spacing for wall and roof panels is governed by the design wind pressure. Common errors: spacing too wide at corners and edges (where pressures are highest), wrong screw type, or missing washers. How to avoid it Corner zones and edge zones need tighter fastener spacing than the field. The drawings will show it. Follow them. The pattern: Most deficiencies happen because someone in the field substituted, skipped, or eyeballed something that the sealed drawings spelled out. The single best prevention is a pre-construction walkthrough where the framer, the GC, and the engineer/inspector go over the load path together. What happens when a deficiency is found The inspector documents the issue, photographs it, and lists it on the WPI-2-BC-8 report. The contractor corrects the issue. The inspector returns for a re-inspection (this is where the $550 re-inspection fee applies). Once the correction is verified, the deficiency is cleared from the open list. Once the open list is empty, the WPI-2E final submittal can move forward. Avoid deficiencies. Hit the schedule. Oasis Engineering inspectors flag issues early —

TDI Forms Explained: WPI-1, WPI-2-BC-8, WPI-2E, WPI-8 | Oasis Engineering Resources · 6 min read TDI Forms Explained: WPI-1, WPI-2-BC-8, WPI-2E, WPI-8 There are four TDI forms in the windstorm inspection process, and they sound almost identical. Here’s a plain-English breakdown of what each one is, when it’s filed, and who is responsible for it — so you can stop confusing them on phone calls. The four forms in order Think of the forms as a timeline, not a list. Each one corresponds to a different moment in the project: WPI-1 — at the start, opens the inspection file WPI-2-BC-8 — during construction, after each inspection WPI-2E — at the end, the final certification package WPI-8 — issued by TDI after review, the actual certificate WPI-1 Application for Certificate of Compliance The starting form. Identifies the project address, owner, builder, and engineer. This is what opens the inspection file with TDI and tells the agency that a windstorm inspection is going to happen on this property. When filedBefore construction Filed byOwner, builder, or engineer Submitted toTDI TriggersInspection eligibility What can go wrong: Filing late. If the WPI-1 isn’t on file before key inspections need to happen, the inspector cannot verify concealed work — and that work may not qualify for certification later. WPI-2-BC-8 Inspection Verification Form This is the form the TDI Appointed Qualified Inspector (AQI) fills out after each inspection during construction. It documents what was inspected, what code provisions apply, design wind speed, exposure category, opening protection requirements, and whether the work conforms to the sealed drawings. When filedAfter each inspection Filed byTDI Appointed Qualified Inspector Submitted toTDI / project file TriggersVerification record What can go wrong: The form requires sealed drawings to reference. If the structure was built without a Texas PE seal on the drawings, this form can’t be properly executed. WPI-2E Engineer’s Certification (Final) The final affidavit submitted by the engineer at the end of the project, certifying that the completed structure complies with the applicable windstorm building code. This is the document TDI reviews to decide whether to issue the WPI-8. When filedAfter final inspection Filed byTexas-licensed PE Submitted toTDI TriggersWPI-8 issuance review What can go wrong: Outstanding deficiencies. If any open items from the WPI-2-BC-8 reports haven’t been corrected and re-inspected, the engineer can’t sign the WPI-2E. The whole closeout stalls. WPI-8 Certificate of Compliance The certificate itself — the document that confirms the structure is eligible for windstorm and hail insurance through TWIA. It is issued by TDI, not by the engineer or inspector, after TDI reviews the WPI-2E and supporting file and finds it complete. When issuedAfter TDI review Issued byTexas Department of Insurance Goes toOwner / property file UseInsurance & lender approval What can go wrong: Incomplete file. If TDI’s review finds missing inspection reports, missing seals, or unresolved deficiencies, the certificate is delayed or denied until the file is cleaned up. Quick reference: WPI-1 opens the file. WPI-2-BC-8 documents each inspection. WPI-2E is the engineer’s final affidavit. WPI-8 is the certificate TDI issues at the end. The first three are work product. The fourth is the prize. Who fills out what This is the other source of confusion — different forms have different signers: WPI-1 can be filed by the owner, builder, contractor, or engineer. Practically, the engineer or inspector files it because they know the form best. WPI-2-BC-8 must be signed by a TDI Appointed Qualified Inspector (AQI). Not just any engineer — only one with the AQI appointment. WPI-2E must be sealed and signed by a Texas-licensed Professional Engineer. WPI-8 is issued by TDI. No signature from your engineer appears on the certificate itself. Why the forms changed in April 2026 TDI updated the WPI-2-BC-8 form effective April 1, 2026 for projects that began construction after that date. The new form references IRC 2024 / IBC 2024 wind load provisions and the latest ASCE 7 design conditions. Older projects use earlier versions of the form referencing the code in effect at the time construction began. If your project straddles the April 1, 2026 cutoff or you’re not sure which version applies, ask your inspector. The wrong form version is a common reason TDI sends a file back for correction. Don’t want to track all four forms yourself? Oasis Engineering handles the entire WPI-1 through WPI-2E process so TDI can issue your certificate. Flat fee. Three site visits. Pay deposit online to start. View WPI-8 service → Related guides What is the WPI-8 Certificate?Plain-English overview of the certificate itself. Common deficienciesWhat inspectors flag most often during construction. Re-roof and retrofit rulesHow form requirements change for non-new-construction. Building without WPI-8The downstream consequences of skipping the path.

What is the WPI-8 Certificate? | Oasis Engineering Resources · 5 min read What is the WPI-8 Certificate? If you’re building in coastal Texas, the WPI-8 is the document that often stands between your project and windstorm insurance, lender approval, and final closing. Here’s what it is — and why it matters — without the bureaucratic fog. The short version The WPI-8 Certificate of Compliance is a document issued by the Texas Department of Insurance (TDI) confirming that a structure in the designated coastal catastrophe area was designed and inspected to meet Texas windstorm building code requirements. If a structure has a WPI-8, it is eligible for windstorm and hail coverage through the Texas Windstorm Insurance Association (TWIA). If it doesn’t, most coastal properties cannot get windstorm insurance — and most lenders will not close on a property without it. The plain-English summary: No WPI-8 → no windstorm insurance → no lender → no closing. That’s why builders, owners, and contractors on the Texas coast need to take it seriously from day one. Where the WPI-8 applies The certificate is required for new construction, additions, alterations, re-roofs, and certain retrofits within Texas’s 14 designated catastrophe-area counties. These are the coastal counties where windstorm exposure is highest: Aransas, Brazoria, Calhoun, Cameron, Chambers Galveston, Harris (partial), Jefferson, Kenedy Kleberg, Matagorda, Nueces, Refugio, San Patricio, Willacy If your project is in any of these counties — or near the coast in a TDI-designated area — windstorm compliance documentation almost certainly applies. Who issues it (and who doesn’t) This is the part that confuses most first-time builders. The WPI-8 certificate is issued by TDI. It is not issued by your engineer, your contractor, your inspector, or your insurance agent. What an engineer or TDI-Appointed Qualified Inspector (AQI) does is the work that supports the certificate: File the WPI-1 application with TDI before construction Inspect the work at key milestones during construction Document deficiencies and verify corrections Submit the final WPI-2E affidavit to TDI Once TDI reviews the package and finds it complete, the agency issues the WPI-8 certificate. That’s why you’ll see careful language on every reputable engineering proposal: “We do not guarantee issuance of the WPI-8. Issuance is subject to TDI review.” It’s not a hedge — it’s accurate. When it matters most There are three moments in a project where the WPI-8 absolutely cannot be missing: 1. Before construction starts The WPI-1 application has to be filed with TDI before work begins, or at least before key inspections need to happen. Filing late means inspectors can’t verify concealed work — and concealed work that wasn’t inspected can disqualify the entire structure from receiving the certificate. 2. During construction Inspections must happen while structural and cladding work is still visible. Foundations get inspected before slab pour. Framing gets inspected before drywall. Cladding gets inspected before final closeout. Miss the window, and the inspector can’t certify what they couldn’t see. 3. At closing Lenders and TWIA both require the WPI-8 for properties in the coastal catastrophe area. Without it, the property is essentially uninsurable for wind — and the loan won’t fund. How long the process takes The WPI-8 process tracks the construction schedule. The application is filed at the start, three to four inspections happen at key stages of the build, and the final submittal goes to TDI after the last deficiency is cleared. Once TDI receives a complete final package, certificate issuance generally takes a few weeks — but timelines vary based on TDI’s review backlog and the completeness of the file. The biggest cause of delay is not TDI. It is missing inspections, deficiencies that weren’t corrected, or drawings that weren’t sealed by a Texas-licensed engineer. A clean file moves quickly. What it costs Cost varies by structure size, complexity, and whether the engineering drawings need to be prepared from scratch or already exist. As a rough benchmark, a productized WPI-8 inspection service for a residential structure runs around $3,000, and a light commercial or metal building runs around $4,500. Custom or large commercial projects are quoted individually. The cost of not doing it right is much higher: a project that gets to closing without a certificate can stall for weeks while the file gets reconstructed — and reconstructed files are harder, because the work that wasn’t inspected during construction may be concealed by then. The bottom line The WPI-8 is not a building department permit. It’s not an insurance policy. It’s a windstorm compliance certificate issued by TDI that confirms a coastal Texas structure meets code requirements for wind. If you’re building anywhere on the coast, plan for it from the first set of drawings — not after the slab is poured. Ready to handle WPI-8 the easy way? Oasis Engineering offers a flat-fee, end-to-end Texas WPI-8 inspection service. Three site visits. One certificate. Pay 50% deposit online and we take it from there. View pricing & buy → Related guides TDI forms explained WPI-1, WPI-2-BC-8, WPI-2E, and WPI-8 without the alphabet soup. Common deficiencies Connection, uplift, and cladding issues that trigger corrections. Building without WPI-8 What happens when the inspection path is missing or incomplete. Coverage map Check whether your project is in the catastrophe area.