When you buy a home in Pennsylvania, the seller is legally required to tell you what they know about the property's condition. That obligation is codified in the Pennsylvania Real Estate Seller Disclosure Law — commonly abbreviated RESDL — enacted in 1996 and last amended under Act 68. The law covers residential properties with up to four dwelling units and requires sellers to complete a standardized disclosure form before the buyer signs the Agreement of Sale.
Understanding RESDL matters for both sides of a transaction. Buyers who know what must be disclosed — and how the "known defects" standard actually works — are better positioned to ask the right questions and verify claims independently. Sellers who understand their obligations avoid costly post-closing litigation. This guide covers what the law requires, what Philadelphia-specific issues it applies to, how the standard is applied in practice, what happens when a seller fails to disclose, and what buyers should do beyond the disclosure form.
Key principle: RESDL requires disclosure of known material defects — it does not require sellers to conduct inspections or to know things they don't know. The law creates a floor of transparency, not a guarantee of condition. A disclosure form that says "unknown" everywhere may be truthful, but it is not the same as a clean property.
The Pennsylvania Association of Realtors (PAR) publishes a standard Seller's Property Disclosure Statement that satisfies RESDL requirements. The form is organized into sections covering the main systems and structural elements of the property. For each item, the seller checks "Yes," "No," or "Unknown," and must provide written explanation for any "Yes" answers.
The form covers the following major categories:
| Section | Key items covered |
|---|---|
| Seller's knowledge of property | How long seller owned it, whether seller currently occupies it, whether it was a rental |
| Structural / roof | Roof age and condition, leaks, repairs, skylights; foundation cracks, settling, water intrusion; load-bearing walls; additions or alterations |
| Basement / crawl space | Water infiltration, seepage, sump pump, prior flooding; radon testing results and mitigation system |
| Termites / wood-destroying insects | Prior infestations, treatment, damage; current pest contract |
| Heating, cooling, plumbing | Type and age of HVAC; known defects; water heater; plumbing leaks; type of pipe (galvanized, copper, PVC, lead) |
| Electrical | Amperage; type of wiring (aluminum, knob-and-tube); known defects; panel age; GFCI presence |
| Sewage / water | Public vs. private sewer; septic system type and last service date; public vs. private water; prior sewer backups |
| Lead-based paint | Known lead-based paint or lead hazards (pre-1978 homes — also covered by federal HUD/EPA disclosure) |
| Environmental hazards | Radon (test results, mitigation); underground storage tanks (fuel oil, gasoline); asbestos-containing materials; mold; hazardous waste sites nearby |
| Legal / zoning | Pending litigation, liens, or assessments; zoning violations or notices; violations or notices from any government agency; open or expired permits; covenant or deed restrictions |
| Other disclosures | Homeowner association membership, fees, and rules; flood zone; Chinese drywall; methamphetamine manufacture history |
The form must be delivered to the buyer before or at the time the Agreement of Sale is signed. If it is not provided, the buyer has the right to rescind the contract within a specified window after receiving it.
The most important thing to understand about RESDL is what it does and does not require. The law covers defects that are actually known to the seller — it does not impose a duty to investigate. A seller who genuinely does not know about a problem is not required to disclose it.
In practice, this creates a spectrum:
Courts in Pennsylvania apply an objective element to the "known" standard: if a reasonable person in the seller's position would have known about the defect — based on its visibility, its duration, or its effect on habitability — the seller cannot escape liability simply by claiming ignorance. This is especially relevant for issues like basement water infiltration, roof damage, and active violations that a seller lived with for years.
Philadelphia context: Many sellers in Philadelphia have lived in their homes for 20–40 years. That tenure increases the likelihood that they are aware of recurring problems — seasonal basement seepage, intermittent roof leaks, the aging boiler that runs poorly — even if those problems were never formally repaired or documented. The disclosure form's "Unknown" box is not a legal shield when the seller has first-hand knowledge.
Several property issues that are common in Philadelphia's aging housing stock appear directly in the RESDL disclosure form, or create disclosure obligations under its general material defects provisions.
The legal section of the disclosure form specifically asks whether the seller has received any notice of violations from a government agency. An L&I violation that was issued and not remediated must be disclosed. Similarly, open or expired permits must be disclosed — buyers inherit permit obligations at closing, and an undisclosed open permit that surfaces post-closing can create significant repair and legal costs.
Sellers sometimes fail to disclose violations because they believe violations were "handled" or because they never followed up after an original notice. Both are risky positions. The Philadelphia Atlas database is public, and any buyer or their attorney can verify violations and permit history independently. Sellers who disclose violations upfront are in a stronger legal position than those whose non-disclosures are discovered during due diligence.
Pre-1978 homes are subject to both federal HUD/EPA lead disclosure requirements and RESDL's own lead section. Sellers must disclose known lead-based paint or lead hazards, provide any existing test results, and include the EPA "Protect Your Family from Lead in Your Home" pamphlet. Philadelphia has additional landlord-specific requirements under its lead paint law, but for sales transactions the federal and RESDL standards apply.
The majority of Philadelphia's housing stock was built before 1978. Lead paint is essentially universal in pre-war rowhouses. Sellers who have had lead inspections or abatement done are required to share those results; sellers without test results typically check "Unknown" for the specific condition of the paint but must still acknowledge the known presence of pre-1978 construction.
The disclosure form has a dedicated radon section. Sellers who have had the property tested must disclose the results. Sellers who have never tested check "Unknown." Pennsylvania is a high-radon state — roughly 40% of homes statewide exceed the EPA action level of 4 pCi/L — and the Piedmont geological zone that covers much of Philadelphia's Northwest is considered elevated risk. See our Philadelphia radon guide for testing methods, mitigation costs, and how to handle radon in a transaction.
Buried oil tanks are common in Philadelphia rowhouses built before 1970, when fuel oil heat was standard. The environmental hazards section of the disclosure form directly asks about underground storage tanks — both active and abandoned-in-place. A seller who knows a tank exists, or who converted from oil to gas and left a tank in the ground, must disclose it. See our underground oil tank guide for detection methods, PA DEP obligations, removal vs. abandonment-in-place, and buyer contract options.
The environmental hazards section also covers asbestos-containing materials. In pre-1980 Philadelphia properties, ACM is essentially ubiquitous — floor tiles, pipe insulation, boiler wrap, joint compound, roofing felts, and more. Sellers who are aware of asbestos in the property must disclose it; sellers without an inspection typically check "Unknown." This is an area where "Unknown" is common and legally defensible, but buyers should understand that an uninspected pre-1980 Philly rowhouse almost certainly has ACM somewhere. Our asbestos guide covers testing, disclosure, and abatement in detail.
The sewage section asks about prior sewer backups and the type of sewer connection. A seller who has experienced sewer backups — even once — must disclose them. Sellers who are aware of aging or damaged lateral infrastructure that has caused problems should disclose. A sewer scope inspection is the buyer's main tool for independent verification, since the seller's disclosure only covers what they know, and lateral deterioration often progresses silently.
The "Other disclosures" section asks whether the property is in a FEMA-designated Special Flood Hazard Area. In Philadelphia, significant portions of Eastwick, riverside neighborhoods near the Delaware and Schuylkill, and properties near Pennypack, Wissahickon, and Cobbs Creeks are in Zone AE or Zone A. Sellers must disclose flood zone status if they know it. Our Philadelphia flood zone guide covers how to look up any property's flood zone and what it means for insurance.
Understanding the law's limits is as important as understanding what it requires. RESDL does not obligate sellers to:
RESDL also does not provide buyers with a warranty of condition. Even a fully and accurately completed disclosure form is not a substitute for independent inspection. A seller can truthfully disclose everything they know, the property can still have significant problems they were unaware of, and the buyer has no legal claim under RESDL in that scenario.
Practical takeaway: Read the disclosure carefully, follow up on every "Yes" and every suspicious "Unknown," and get independent inspections. The disclosure form is a starting point for due diligence, not a finish line.
Some Philadelphia properties — especially estates, foreclosures, and investor flips — are sold "as-is." Buyers often assume this means the seller has no disclosure obligation. That is incorrect.
An as-is sale in Pennsylvania does not waive RESDL disclosure requirements. The seller of an as-is property is still required to complete and deliver the disclosure form. What "as-is" means is that the seller is not agreeing to make any repairs — it does not mean the seller can withhold known material defects from the buyer.
Courts have consistently held that fraudulent concealment claims survive an as-is clause. If a seller actively hid a problem, or completed the disclosure form knowing it was false, the as-is language in the Agreement of Sale does not protect them from liability.
For buyers purchasing as-is properties — particularly foreclosures, probate sales, and REO properties — there is an additional complication: estate and bank sellers often have little or no knowledge of the property's condition, making "Unknown" throughout the disclosure technically truthful. In these cases, independent inspection and city records verification become even more critical, since there may be no actionable disclosure claim if problems are discovered after closing.
RESDL requires the disclosure form to be provided before or at the time the buyer signs the Agreement of Sale. The standard PAR transaction timeline works like this:
When a seller fails to disclose a known material defect — or actively misrepresents a condition in the disclosure form — buyers have several potential legal remedies:
| Remedy | When it applies | Typical outcome |
|---|---|---|
| Rescission | Discovered before closing; seller fails to disclose before or at signing | Contract voided, deposits returned |
| Damages (RESDL) | Post-closing discovery of known defect not disclosed | Cost of repair, diminution in property value |
| Fraud / misrepresentation | Seller actively concealed or affirmatively misrepresented a condition | Actual damages + potentially punitive damages |
| Breach of contract | Disclosure was incorporated into the Agreement of Sale as a warranty | Repair cost, market value differential |
| Real estate agent liability | Agent knew of defect and failed to disclose | Agent + broker liability, license action |
The statute of limitations for RESDL claims in Pennsylvania is generally two years from the date the buyer discovered or reasonably should have discovered the undisclosed defect, not two years from closing. For latent defects that are not immediately apparent — basement waterproofing failures that only manifest in wet seasons, for example — the clock may not start running until the first time the problem becomes visible.
In Philadelphia, buyers who discover post-closing that a seller failed to disclose known L&I violations or open permits have an especially strong evidentiary position, because these records are public. A seller who had an outstanding violation notice in their name cannot credibly claim they were unaware of it.
One of the most important due diligence steps for any Philadelphia buyer is pulling city records independently — not as a substitute for the disclosure, but as a cross-check. Several Philadelphia databases make this straightforward:
Run a free Flagstone report on any Philadelphia address to instantly pull L&I violations, permit history, 311 complaints, OPA records, and tax status — the same public records that should be consistent with a seller's disclosure.
Run a Free Property ReportFor sellers, the best protection is thorough, honest disclosure. The legal exposure from non-disclosure — especially for issues that are documentable in public records — far exceeds the risk of a buyer walking away over a disclosed defect. Most disclosed defects result in price adjustments, repair credits, or seller-side repairs, not lost deals. Undisclosed defects that surface post-closing can result in litigation that costs multiples of what disclosure would have cost.
Practical steps for sellers:
The disclosure form is the seller's representation of what they know. It is not a substitute for the buyer's own investigation. For any Philadelphia property, buyers should treat the following as standard practice:
| Step | What it covers | Where to do it |
|---|---|---|
| Pull city records on Atlas | L&I violations, permit history, 311, OPA, tax delinquency | atlas.phila.gov — free |
| Verify permits on eCLIPSE | Open/expired permits, permit conditions, inspection status | eclipse.phila.gov — free |
| Standard home inspection | Structural, roof, HVAC, electrical, plumbing, visible defects | ASHI/InterNACHI-certified inspector |
| Sewer scope (pre-1960 properties) | Sewer lateral condition — not covered by standard inspection | Licensed plumber with camera equipment |
| Radon test (all properties) | Short-term charcoal canister test during inspection period | PA DEP certified radon tester |
| Lead paint inspection (pre-1978) | Condition and risk of known lead-based paint | EPA-certified lead inspector |
| Oil tank scan (pre-1970 rowhouses) | Presence of buried heating oil tanks | Magnetometry survey by environmental firm |
| Title search | Mechanics liens, judgment liens, PWD liens, deed history | Title company — required for most lenders |
For a complete framework across all nine due diligence layers, see our Philadelphia property due diligence checklist.
Use this checklist when reviewing a Pennsylvania seller disclosure form on a Philadelphia property:
Pennsylvania's RESDL creates a baseline of transparency in real estate transactions: sellers must disclose what they know, and buyers have legal remedies when sellers conceal known material defects. In Philadelphia, where the housing stock is old and city records are publicly accessible, the standard disclosure form intersects with a specific set of issues — L&I violations, open permits, lead paint, radon, buried oil tanks, asbestos, sewer conditions, and flood zone status — that buyers should verify independently regardless of what the form says.
The disclosure is a starting point. Independent inspection, city records verification, and — for pre-1960 properties — specialized testing for radon, sewer condition, and environmental hazards are the layers that give buyers genuine knowledge of what they are buying.