What Do Inspectors Look For in a Home Inspection: Guide
Asking what do inspectors look for in a home inspection has a layered answer because no two credentialed inspectors weight the same property identically. The ASHI and InterNACHI Standards of Practice establish a minimum floor that every credentialed inspector must meet. Above that floor, individual inspectors emphasize different categories based on their background (former roofer, former electrician, former contractor), the regional housing stock they have worked on for years, and the add-on services they have invested time in mastering. This guide explains the minimum floor in detail, then explores the inspector-variability angle so buyers understand why the same property can produce two slightly different reports.
The minimum scope every credentialed inspector covers
The minimum scope is fixed across the industry. Both ASHI and InterNACHI publish Standards of Practice that require a credentialed inspector to evaluate ten functional categories on a visual, non-invasive basis: roof, exterior, structure and foundation, plumbing, electrical, heating, cooling, interior, insulation and ventilation, and built-in appliances. The scope is the floor, not the ceiling. Any inspector advertising ASHI or InterNACHI membership commits to delivering at least this level of evaluation on every appointment.
The visual, non-invasive constraint means inspectors do not open walls, lift permanently affixed flooring, or move stored items to access systems. The buyer pays for what is readily visible and safely accessible on the day of the appointment. This guide reflects ASHI and InterNACHI guidance current as of 2026; site-specific scope varies with accessibility.
How inspector backgrounds influence emphasis
Inspectors enter the profession from varied prior careers, and the prior career shapes what gets extra attention. A former licensed electrician working as an inspector spends more time on the panel and branch-circuit sampling than a former carpenter would. A former roofer walks the surface more aggressively, photographs more roof anomalies, and gives more nuanced remaining-life estimates than a generalist who inspects from the eave. A former HVAC tech notices subtle furnace combustion-air problems and inadequate return-air sizing that generalists may miss. A former general contractor brings a broader systems-view but may lean less deep on any individual category.
None of these backgrounds make one inspector better than another in absolute terms. They make individual inspectors stronger or weaker in specific categories. Buyers with concerns about a particular system (older roof, suspect electrical, complex HVAC) benefit from asking inspectors about their prior trade experience.
What every inspector looks for: roof
The roof check looks for shingle condition (granule loss, curling, missing tabs, exposed nail heads), flashing at chimney and wall transitions, vent boot integrity, gutter slope and securement, soffit and fascia condition, and visible past-repair evidence. On membrane and tile roofs the inspector looks for seam separation, cracked tiles, displaced units, and UV degradation. Skylight curbs and flashing get separate attention.
An inspector with roofer background may walk the entire accessible surface; a generalist may inspect from a ladder at the eave. Both are within standard practice. The report should disclose which method was used and what conditions prevented full surface inspection.
What every inspector looks for: structure and foundation
The structural check looks for foundation type, visible cracking patterns, settlement evidence, framing condition where accessible, and any sagging or deflection in joists or beams. Vertical hairline cracks in poured concrete are typically shrinkage; horizontal cracks, step cracks in block walls, and rotational displacement are escalation triggers. Crawl spaces get entered when access is safe.
An inspector with carpentry background notices framing-related issues more readily; an inspector with masonry background reads foundation cracks more nuanced. Both are well within scope. The companion guide on what inspectors look for in a home inspection covers the same scope from the singular-inspector framing.
What every inspector looks for: plumbing
The plumbing check looks for supply-line material, visible leaks at supply and drain connections, water-heater age and TPR-valve discharge, main shutoff location, fixture function, and any visible cross-connections. Galvanized supply lines in pre-1970s homes get a corrosion-progression note. Polybutylene grey supply pipe (homes built 1978 to 1995) gets flagged for known failure history. Lead solder joints in pre-1986 copper systems are noted as a water-quality concern.
An inspector with plumbing background may sample more fixtures and identify specific failure modes faster. A generalist still meets the SoP floor.
What every inspector looks for: electrical
The electrical check looks for service capacity, panel condition, branch-circuit sampling at receptacles and switches, GFCI and AFCI protection where required, bonding and grounding, and smoke and CO alarm presence. Federal Pacific Stab-Lok, Zinsco, and certain Challenger panels are flagged regardless of current condition because of recall history. Open neutrals, reversed polarity, and double-tapped breakers are common findings.
An inspector with electrician background reads the panel more deeply and identifies subtle issues (improper neutral-ground bonding in a sub-panel, wrong wire gauge for breaker rating) that generalists may miss. The hiring-a-home-inspector hub covers how to ask about an inspector’s background during the interview.
What every inspector looks for: HVAC
The HVAC check operates the system at normal controls, observes supply and return temperatures at a sample register, examines visible ductwork and filter condition, looks at flue connections and combustion-air provisions, and reads equipment data plates for age and rated capacity. Cooling is operated only when outdoor temperatures allow safe testing (above 60 degrees F). Heat exchangers in furnaces are checked visually through accessible panels; full disassembly is outside scope.
An inspector with HVAC background identifies improper return-air sizing, combustion-air shortfall, and condensate-line slope issues faster. The generalist meets the SoP floor; the specialist provides more diagnostic depth.
What every inspector looks for: interior and built-ins
Interior checks look for wall, ceiling, and floor condition, window operation, interior door condition, stair and railing safety, and a representative sample of receptacles and switches. Built-in appliances (range, oven, dishwasher, built-in microwave, exhaust hood, garbage disposal) are operated on a normal cycle. The check stops at appliance function; warranty status, repair history, and remaining service life are typically not graded.
The interior check is where buyer self-walkthroughs cover more ground than other categories. The inspector’s value here is in the systematic walk and the photography, not in finding hidden problems.
Where inspector-to-inspector variability shows up
Variability shows up most in how findings are graded and described. Two credentialed inspectors looking at the same vertical hairline crack in a poured-concrete foundation may both note it; one may grade it Monitor, the other may grade it Repair if local soil conditions suggest active settlement. Two inspectors looking at the same 18-year-old furnace may both note the age; one may suggest budget for replacement in 24 months, the other in 60 months. Neither is wrong; both are within the SoP’s bounds.
Variability also shows up in narrative depth. Some inspectors write three sentences per finding; others write half a paragraph with context, photograph references, and recommendations. Buyers comparing inspectors by sample report will see this difference clearly.
How to read a report when two inspectors disagree
Buyers occasionally hire a second inspector when the first report raises concerns the buyer wants verified. The two reports will not be identical. Treat the overlap as the consensus finding; treat the differences as the variability inherent in the profession. Categories where both inspectors flagged a Safety or Repair item belong on the negotiation list. Categories where the inspectors split usually warrant a third specialist (structural engineer, HVAC contractor, electrician) for the deciding evaluation.
Two inspections cost more than one but rarely waste money on a high-stakes purchase. The companion guide on what they look for in a home inspection covers the walkthrough-sequence angle.
What stays outside any inspector’s scope
Outside scope regardless of inspector background: environmental hazards (radon, mold, asbestos, lead) unless contracted separately, geotechnical soils, code-compliance certification, swimming pools in some jurisdictions, low-voltage systems, cosmetic finish judgments, and concealed conditions. Front Range buyers contract a radon measurement separately because Colorado sits in EPA Zone 1. Pre-1978 homes often add a lead-paint test. The standard report does not change with inspector expertise on these items; they require separate sampling protocols.
How experience volume changes what gets flagged
Total inspection volume matters as much as background. An inspector who has personally performed 3,000 inspections has seen patterns a 200-inspection inspector has not. Volume builds pattern recognition: the inspector with five years on similar housing stock notices the subtle stucco-flashing failures specific to a builder, the recurring drain-line slope issues in a subdivision, or the panel-bonding errors a regional electrical contractor made decades ago. Volume also builds judgment about what to grade Safety versus Repair versus Monitor.
Buyers benefit from asking inspectors directly how many homes they have personally inspected in your zip code. The number is a reasonable proxy for how confidently the inspector will navigate your specific property. Volume in a different metro area transfers partially; volume in your subdivision transfers fully.
Add-on services and what specialist tools add
Add-on services expand the scope beyond the standard ten categories. Thermal imaging adds a non-contact infrared scan that surfaces missing insulation, air leakage at top plates, and moisture patterns invisible to a visual scan. Sewer scope adds a camera inspection of the lateral from the cleanout to the city tap, surfacing root intrusion, belly sags, and cracked or collapsed sections. Moisture mapping with a pin or pinless meter quantifies elevated readings around tubs, windows, and exterior walls.
Each add-on requires the inspector to invest in specific equipment and training. An inspector who advertises thermal imaging as an add-on without showing sample thermal-scan reports may be running a marketing checkbox rather than a meaningful service. Ask for a sample of the add-on deliverable before paying for it. Quality varies substantially across the industry on add-ons; the credential covers the base scope but not necessarily the specialty.
What buyers should expect from the verbal walkthrough
Most credentialed inspectors offer a verbal end-of-appointment summary at the property. This is the buyer’s chance to walk the property with the inspector, see the largest findings in context, ask questions, and form a mental map of the home’s condition before the written report arrives. The verbal walkthrough is usually 20 to 45 minutes depending on report findings. Inspectors who skip the verbal summary are doing the buyer a disservice; ask for it explicitly when scheduling.
Bring a notebook and a phone. Photograph anything the inspector points at because you will not retain the verbal context once you are home reading the PDF. Ask the inspector to flag the three findings they consider most consequential. The answer often differs from the photo-heavy first impression a written report creates.
Final pre-closing verification
Even after the inspection report is written and the objection negotiation closes, buyers benefit from a final walkthrough the day before or morning of closing. Verify that any repairs the seller agreed to complete have been completed and that documentation is provided. Confirm utilities are still on, fixtures still operate, and no new damage has appeared during the seller’s move-out. The final walkthrough is not a re-inspection; it is a verification step against the inspection report and the contract.
References
- ASHI Standard of Practice — American Society of Home Inspectors
- InterNACHI Residential Standards of Practice — International Association of Certified Home Inspectors
- EPA radon program overview — U.S. Environmental Protection Agency
- HUD home inspection program — U.S. Department of Housing and Urban Development