Pennsylvania Home Inspection Guide

Radon — Pennsylvania's Most Serious Invisible Hazard

Pennsylvania is one of the radon-highest states in the United States. The EPA estimates roughly 40% of Pennsylvania homes exceed the 4 pCi/L action level. The primary geological driver is the limestone belt running diagonally across the state from Adams and York counties in the south through Lancaster, Lebanon, Dauphin, and Berks counties to Northampton and the Lehigh Valley — and continuing into Monroe County and the Poconos. Limestone is limestone-karst terrain, where uranium-rich rock decays to radium and then to radon gas that migrates freely through soil and into homes. Radon testing in Pennsylvania is not a precaution — it is a standard part of every home purchase. The good news: radon mitigation systems are effective and available throughout PA for $800–$2,000. Sellers are accustomed to radon mitigation as a standard inspection finding.

Old Knob-and-Tube Wiring

Pennsylvania's housing stock is among the oldest in the country. Philadelphia row homes built from the 1890s through the 1930s frequently still contain original knob-and-tube (K&T) wiring, either fully intact or mixed with later updatedwork. K&T wiring uses ungrounded two-conductor circuits with ceramic insulators and lacks any ground fault protection. Decades-old insulation on K&T wire becomes brittle and prone to cracking. The bigger practical problem is insurance — most Pennsylvania homeowners insurance carriers will not write a new policy on a home with active K&T wiring, or will require an electrical inspection and potentially full rewiring before coverage begins. Full rewiring of a 1,500 sq ft Philadelphia row home typically costs $8,000–$15,000. For larger older homes and twin houses, costs can reach $20,000.

Asbestos and Lead Paint in Pre-1980 Homes

Pennsylvania's old housing stock means asbestos and lead paint are common facts of life in PA real estate. Asbestos was used in floor tiles, pipe insulation, boiler jackets, duct insulation, plaster, and cement board siding. Lead paint was used on virtually all painted surfaces in homes built before 1978. A general home inspector will note suspect materials that visually appear to be asbestos-containing or note the age of the home as sufficient to presume lead paint presence — but the inspector is not qualified to confirm or test for either material. For pre-1978 Pennsylvania homes, budget separately for asbestos sampling ($400–$800) and lead paint testing ($150–$400) if those hazards are a concern. If you are purchasing with an FHA loan, lead paint on deteriorated surfaces is a mandatory repair item.

Basement Moisture and Old Oil Tanks

Pennsylvania homes, far more than those in southern states, typically have full basements with stone, brick, or early poured concrete walls. These older foundation systems lack modern waterproofing and allow moisture migration. Inspectors look for efflorescence (white mineral streaks indicating ongoing water movement through masonry), staining, spalling concrete, and any evidence of active seepage. In neighborhoods built before 1970 that originally used fuel oil heat, abandoned above-ground and buried oil storage tanks are common. An above-ground tank that has been decommissioned but left in place is a manageable issue. A buried oil tank is a potentially significant environmental liability — soil contamination from a leaking buried tank can cost $20,000–$100,000 to remediate. Ask the seller directly about oil tank history and request documentation of removal or decommissioning.

Stone and Brick Foundation Condition

Philadelphia-area row homes, colonial-era farmhouses in Chester and Lancaster counties, and Victorian homes throughout Pittsburgh and Allegheny County frequently sit on stone rubble or brick foundations laid in lime mortar. This construction has durability advantages — many 150-year-old stone foundations remain structurally sound. However, mortar joints deteriorate over time and allow water infiltration, and settlement cracks in older stone foundations can be significant. Inspectors examine foundation walls in the basement for bowing, cracking, wet spots, and degraded mortar joints. Significant structural concerns in a stone or brick foundation require evaluation by a structural engineer experienced with historic masonry construction.

No. Pennsylvania is one of a small number of states that does not require home inspectors to hold a state license. This makes professional certifications from ASHI (American Society of Home Inspectors) or InterNACHI (International Association of Certified Home Inspectors) critically important for Pennsylvania buyers. These organizations set educational standards, require examination, mandate continuing education, and enforce a code of ethics. Hiring an uncertified home inspector in Pennsylvania carries significant risk — there is no state board to file a complaint with and limited legal recourse if work is substandard.

Pennsylvania consistently ranks among the highest-radon states in the country. The geology of eastern and central Pennsylvania — particularly the limestone belt stretching from York County through the Lehigh Valley and into the Pocono region — contains abundant uranium and radium that decay into radon gas. This gas migrates up through soil and enters homes through foundation cracks, slab penetrations, and crawl spaces. The EPA estimates that approximately 40% of Pennsylvania homes have radon levels above the action threshold of 4 picocuries per liter (pCi/L). Radon testing is not optional in Pennsylvania — it is essential.

Knob-and-tube (K&T) wiring is the electrical system installed in American homes from roughly 1880 through the 1940s. It uses ceramic knobs to support wiring through framing and ceramic tubes where wires pass through framing. Pennsylvania has one of the oldest housing stocks in the country — Philadelphia row homes from the 1890s through 1920s regularly still contain K&T wiring. The problems: K&T has no ground wire (making it incompatible with modern appliances), its insulation degrades and becomes brittle over decades, and it is frequently overloaded when attic insulation is added over it. Most home insurers will not cover homes with active K&T wiring, or will charge significantly higher premiums. Full rewiring of a Pennsylvania row home can cost $8,000–$20,000.

Highly concerned if the home was built before 1980. Asbestos was used extensively in Pennsylvania residential construction — most commonly in floor tiles (9x9 and 12x12 vinyl floor tiles), pipe insulation on steam and hot water pipes, duct insulation, boiler insulation, plaster textured ceilings, and siding (Transite). A general home inspector can identify suspect materials but is not typically qualified to confirm asbestos content — that requires laboratory sampling. For pre-1980 Pennsylvania homes, budget $400–$800 for a separate asbestos survey by a certified asbestos inspector. Abatement costs vary widely depending on scope and material type.

Pennsylvania homes, particularly in Philadelphia and surrounding counties, are far more likely to have full basements than homes in southern or western states. Basements in older PA homes made of stone foundation walls, brick, or early poured concrete are prone to moisture intrusion, efflorescence (white mineral deposits from water migration), and in some cases, structural bowing or cracking. Old oil tanks — both above-ground and buried underground — are common in pre-1980 Pennsylvania homes that converted from oil heat to gas. An abandoned buried oil tank is a significant liability requiring environmental assessment.