Things That Fail a Home Inspection: A Guide for Inspectors

Short answer: A home inspection has no pass or fail. What buyers call "failing" is a finding that is significant enough to change the deal: a roof at the end of its life or leaking, electrical hazards such as double-tapped breakers, certain panel brands and pre-1972 aluminum branch wiring, active plumbing leaks, old or failing HVAC equipment, structural cracks, water intrusion, and missing safety devices. Your job is to report each one as what you saw, why it matters and what to do, with the location and a photo, so the finding holds up when someone reads it closely.

Buyers search "what fails a home inspection" because they think of it as a test. You know it is not. But the question points at something real: a short list of conditions drives many of the repair requests, credits and walked deals. Those are the findings a buyer, an agent and occasionally an attorney will read most carefully. This guide covers what they are and how to write them.

There is no pass or fail, so what counts as significant?

The standards of practice define what you report, and neither of the main national standards uses pass or fail.

InterNACHI's Standards of Practice define a material defect as "a specific issue with a system or component of a residential property that may have a significant, adverse impact on the value of the property, or that poses an unreasonable risk to people." They add a line inspectors should remember: "The fact that a system or component is near, at, or beyond the end of its normal, useful life is not, in itself, a material defect."

The ASHI Standard of Practice requires the report to state systems and components that, in the inspector's judgment, "are not functioning properly, significantly deficient, unsafe, or are near the end of their service lives," with recommendations to correct or monitor, and reasoning where the deficiency is not self-evident.

In practice, the findings that change a transaction fall into three groups: safety hazards, active damage or failure (a leak, a structural crack, equipment that does not run), and major components near the end of their service life. The rest is maintenance. Your report should make the difference obvious.

If your state has its own standards or a required report form, those govern. Know what inspectors are not allowed to do under your standard too, because overreach creates as much exposure as a miss.

The conditions that most often become significant findings

The rest of this guide takes each area in turn.

Roofs: report condition, and give age as information

Buyers expect bad news about the roof, and it is where inspectors get into trouble by predicting.

Report what you observed: missing, lifted, cracked or damaged covering; exposed fasteners; granule loss; failed or missing flashing at chimneys, walls and penetrations; staining or active moisture in the attic below; soft decking if you walked it. State how you inspected it (walked, from a ladder at the eave, by drone, from the ground with binoculars) and why, because a limitation described at the finding is worth more than one buried in the agreement.

Age belongs in the report as information, not as a forecast. InterNACHI's estimated life expectancy chart lists architectural asphalt shingles at about 30 years and 3-tab asphalt shingles at about 20, and says the figures "should be used as guidelines only, and not relied upon as guarantees or warranties." It also notes hot climates "drastically reduce asphalt shingle life." You can state that a covering appears to be near or beyond the typical range for its type without promising how many years remain. Our guide to writing defect comments that hold up explains why you should never estimate remaining life.

Roof age and condition also drive insurance. In markets where insurers ask for a 4-point inspection, the roof is one of the four systems they look at.

Electrical: double taps, problem panels and aluminum wiring

Double-tapped breakers

Most breakers are designed for one conductor per terminal. InterNACHI's panel inspection article explains the concern: the connection "is not designed for two wires," so one or both may not be secure, which can lead to a loose connection or arcing. Some breakers are listed for two conductors, and InterNACHI names certain Square D QO models as UL-listed for two. Check the breaker's markings before you call it a defect, and say in the comment that you did.

Double-lugged neutrals on the neutral bar are a separate finding. InterNACHI notes that current versions of the National Electrical Code prohibit more than one neutral conductor under a single terminal.

Federal Pacific Stab-Lok and Zinsco panels

These panels generate strong opinions, so word the finding carefully and cite your basis. The Consumer Product Safety Commission investigated Federal Pacific Electric Stab-Lok breakers and closed the investigation in 1983. Its 1983 release said the available data did not establish a serious risk of injury and that fully assessing the breakers would cost several million dollars it chose not to commit, and a CPSC staff note on the release says the matter was closed "without making a determination as to the safety of FPE circuit breakers." InterNACHI's panelboard article says breakers in these panels fail to trip "at rates far higher than industry standards" and recommends replacement of the panelboard.

A comment that holds up names the panel, states that the brand has a history of reported problems, recommends evaluation by a licensed electrician, and does not claim the panel has failed unless you observed failure.

Aluminum branch wiring

The CPSC's Publication 516 reports that a national survey for the agency found homes built before 1972 and wired with aluminum were "55 times more likely to have one or more wire connections at outlets reach 'Fire Hazard Conditions'" than homes wired with copper. It warns that failing aluminum connections "seldom provide easily detected warning signs."

As of that publication, CPSC recognizes three permanent repairs: rewiring with copper, the COPALUM crimp method, and AlumiConn connectors. It says pigtailing with twist-on connectors "is not a recommended repair," and calls CO/ALR devices "at best, an incomplete repair." InterNACHI's standards require you to report readily visible solid-conductor aluminum branch-circuit wiring as in need of correction. Recommend evaluation by an electrician qualified in the CPSC-recognized methods.

GFCI protection and receptacles

InterNACHI's standards require testing receptacles and GFCIs where possible and reporting receptacles with no power, incorrect polarity, missing covers, GFCI devices that are not installed properly or do not operate, or signs of arcing or overheating.

Missing GFCI protection in an older home is common and easy to misreport. The CPSC's GFCI fact sheet lists when the National Electrical Code first required GFCI receptacles: outdoors in 1973, bathrooms in 1975, garages in 1978, kitchens in 1987, and crawl spaces and unfinished basements in 1990. It also notes the NEC typically applies to new construction and major renovation. So report missing protection at wet locations as a safety upgrade to consider, not as a code violation in a house built before the requirement.

Plumbing and water heaters

Active leaks under sinks, at supply connections and at the water heater are straightforward findings: location, evidence, a moisture reading if you took one, and a plumber.

Polybutylene supply piping needs more care. InterNACHI says it was manufactured from 1978 to mid-1995 and installed in up to 10 million U.S. homes, and that deterioration "happens from within." It also states that home inspectors are not required to note polybutylene. If you do report it, report it as identified material with a known history, recommend a licensed plumber evaluate it, and do not claim you tested it.

Water heaters are a common age finding. InterNACHI's chart lists conventional tank water heaters at 6 to 12 years. Read the serial number for the manufacture date, state the age, note corrosion or leaks, and check the temperature and pressure relief valve and venting, which InterNACHI's standards include in the water heater inspection.

If the sewer lateral is a concern, a sewer scope inspection is the separate service that answers it.

HVAC: age alone is not a defect, failure is

A furnace that does not fire or an air conditioner that does not cool is a significant finding. So are cracked or disconnected vent connectors and signs of combustion problems.

Age is the area where wording matters most. InterNACHI's chart gives furnaces 15 to 25 years, central air conditioners 7 to 15 and heat pumps 10 to 15, all as guidelines. Report the manufacture date from the data plate, that the unit is at or beyond the typical range for its type, whether it operated when tested, and a recommendation to have it serviced and evaluated by an HVAC contractor. Under InterNACHI's definition, age alone is not a material defect; under ASHI's, a component near the end of its service life is still reportable. Both are satisfied by a finding that reports age as a fact and function as observed.

Foundations and structure

Foundation findings are the ones buyers fear most and the ones most often overstated or understated.

InterNACHI's article on inspecting masonry says horizontal cracking in a foundation wall "is potentially serious because it indicates that the foundation wall... is basically bent or broken," and lists causes such as improper backfilling, heavy vibration, and frost or saturated soil pressure. Its foundation maintenance article, writing about concrete slabs, says large cracks, greater than a quarter inch, "should be evaluated by an expert, especially if any buckling or warping of walls or floors is also present."

Describe the crack: location, orientation, approximate width, any displacement, and whether there are related signs such as sticking doors, sloping floors or bowing walls. Recommend a structural engineer for anything beyond minor shrinkage cracking. You are reporting evidence, not diagnosing cause or prescribing a repair.

Water intrusion

Water causes more downstream damage than almost anything else you report. Look for staining, efflorescence, rust on fasteners, elevated moisture meter readings, standing water in crawlspaces, and the causes outside: negative grading, short or missing downspout extensions, clogged gutters, failed flashing.

Link cause and effect in the report where you can see both. "Staining and elevated moisture readings at the northeast basement wall. Downspout at the northeast corner discharges at the foundation. Recommend extending the downspout and monitoring; evaluation by a qualified contractor if moisture persists." That reads as an observation, not a guess, and gives the buyer a next step.

Safety items that are easy to report and easy to miss

• Smoke alarms. The U.S. Fire Administration says to "replace the entire smoke alarm every 10 years." InterNACHI's standards require reporting the absence of smoke and carbon monoxide detectors. Note alarms that are missing, and where you can read a date, ones past ten years.
• Carbon monoxide alarms. CPSC recommends CO alarms "on every level of the home and outside sleeping areas," and reports that more than 200 people die each year in the U.S. from accidental non-fire CO poisoning linked to consumer products. Report missing CO alarms in homes with fuel-burning appliances or an attached garage.
• GFCI protection at wet locations, covered above.
• Guards, handrails and stairs, and decks, where loose or missing components are a fall hazard.

These are short comments, but a buyer who moves in and has a CO event will read yours.

How to document and word findings so they hold up

A significant finding will be read by a buyer, their agent, the seller's agent, a contractor, and sometimes an attorney. Write it for the most skeptical of them. Every comment should state what you saw, where, why it matters and what to do, in that order, as covered in writing defect comments that hold up.

Three habits make the difference:

1. Photograph the evidence, not the component. A close photo of the double-tapped lug, annotated with an arrow, beats a photo of the whole panel.
2. Put location and measurement in the text. "North basement wall, 3/8 inch" survives a dispute; "crack in basement" does not.
3. Put the limitation at the finding. If you could not remove the panel cover or walk the roof, say so where the reader will see it.

Consistency matters as much as wording. If two inspectors in your company describe the same double tap differently, the weaker version is the one that ends up in a complaint. Agents notice inconsistency too. If a finding does become a dispute, see can you sue a home inspector for how claims usually unfold.

Using a comment library for the findings you write every week

The findings in this guide come up again and again, which makes them ideal for a comment library: vetted wording you reuse and adjust for each house, instead of rewriting at 7 p.m. from memory.

Binsr's comment library holds 12,000+ comments and templates written by inspectors, and you can add your own. Search is semantic, so typing "two wires on one breaker" finds your double-tap comment even if it is worded differently, and usage tracking shows which comments you rely on. On Pro, AI in the report builder drafts and rewrites findings from your own dictation, photos and comment library; you review every word. Our guide to building a comment library covers how to set one up.

Frequently asked questions

Keep reading

• How to write defect comments that hold up
• How to build a home inspection comment library
• What agents want from an inspection report
• What home inspectors are not allowed to do
• Can you sue a home inspector?

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