The home inspection process: what inspectors actually check (and what they don’t)

A home inspection is a generalist visual examination. It is not a guarantee, not a code inspection, and not destructive testing. The inspector cannot open walls, dig in the yard, or test things they can’t see. Their job is to spot visible defects and flag things that warrant specialist follow-up.

Whether the inspector is “licensed” depends on your state. Roughly 35 states require licensing; the rest (including IL in some respects, CO, KS, ME, WY, and others historically) don’t regulate inspectors at all. In unregulated states, the only quality filter is professional membership — ASHI (American Society of Home Inspectors) or InterNACHI, both of which require testing, continuing education, and a Standards of Practice. Check credentials before hiring; “home inspector” by itself means nothing in half the country.

Understanding what’s in scope — and what isn’t — is the difference between a useful inspection and a false sense of security.

Cost and timeline

• Single-family home: $400-700 (typical)
• Larger / 4+ bedroom / multi-story: $600-900
• Multi-unit (2-4): $800-1,500 (each unit inspected)
• Add-ons (sewer scope, radon, etc.): $100-600 each

The inspection itself takes 2-4 hours on-site for a standard SFH. The written report typically arrives the next business day, though many inspectors deliver same-day for an extra fee.

What a standard ASHI/InterNACHI inspection covers

The two main professional standards (ASHI and InterNACHI) define what a competent inspection includes. Their scopes are nearly identical:

• Roof — the SoP says inspectors must inspect the roof, but the method is their call. Walk-on if safely accessible, ladder at the eaves if steep/tall, binoculars from grade if wet/icy/ unsafe, or drone (now common — many inspectors fly a DJI for any roof over a single story). Ask up-front which method yours uses; ground-only on a complex roof misses a lot.
• Exterior — siding, trim, fascia, soffits, drainage and grading away from foundation, decks, patios, walkways
• Foundation — visible cracks, water staining, basement waterproofing, sump pump operation. Crawlspaces are inspected if accessible — standing water, active vermin, sub-18-inch clearance, or fresh sewage will get the entry noted as “not inspected, hazardous conditions” and that’s legitimate per SoP. If your inspector skips the crawl, ask why and whether a specialist needs to crawl it.
• Structural — visible framing in attic and basement, signs of sagging, settling, or repair
• Plumbing — visible supply and drain pipes, fixtures, water pressure, water heater age and condition
• Electrical — main panel, breaker labeling, sample of outlets, GFCI/AFCI testing in required locations, visible wiring
• HVAC — furnace, AC, ductwork. AC is not tested when outdoor temperature is below ~65°F (you can damage the compressor). Heat is not tested in the height of summer.
• Appliances included with the sale — basic operation
• Windows, doors, walls, ceilings, floors — condition, seals, visible damage
• Insulation and ventilation in accessible attic spaces
• Garage — door operation, auto-reverse safety, firewall

What it DOES NOT include (but you often need)

The standard inspection skips these — you have to specifically order them, often through specialists:

• Sewer scope ($150-300): camera run through the main sewer line to the street, usually pulled out of a clean-out or vent. Always get one for any home built before ~1980 — cast iron, Orangeburg (1945-1972), and clay tile fail catastrophically. Replacement runs $5,000-25,000+; trenchless lining is cheaper but not always viable.
• Radon test ($100-150 short-term, $200-400 long-term): the short-term 48-96 hour charcoal/electret test is what most buyers run because of contract timing, but it’s a snapshot — readings vary day-to-day with weather and HVAC. A long-term (90+ day) test is what the EPA actually recommends for an accurate average. EPA action level: 4.0 pCi/L; consider mitigation at 2.7+. Mitigation runs $1,000-2,500.
• Mold testing ($300-600): home inspectors can identify suspected mold visually but can’t confirm species or levels — that’s a separate IAQ specialist (industrial hygienist or certified mold assessor) doing air samples and tape lifts to a lab. Don’t let an inspector “test mold” with a swab kit; it’s outside their scope.
• Pest / termite / WDO inspection ($75-150): a separate licensed pest operator filling out Form NPMA-33 (the “termite letter”). Required by VA in most states (and the seller usually pays per VA rules) and by FHA when the appraiser flags evidence. In termite-active states (Southeast, TX, CA, HI) always get one whether the loan demands it or not.
• Pool/spa inspection ($150-300): pump, filter, heater, plumbing pressure test, surface (plaster/liner), decking, bonding, and safety features (4-sided isolation fence, self-latching gate, Loop-Loc cover, anti-entrapment drain covers per VGB Act)
• Septic inspection ($300-600): includes tank pumping so the inspector can see the baffles and floor, plus a drain-field loading test. Required by FHA on many private systems and by most rural conventional lenders. A “dye test” alone is not adequate.
• Well inspection / water test ($100-300): bacteriological (coliform, E. coli), nitrates, nitrites, lead, and in some regions arsenic, fluoride, or radon-in-water. FHA and VA require well water testing; conventional often does too on private wells. Also: flow rate (gpm) and pressure tank function.
• Chimney and fireplace ($100-300): Level 2 chimney inspection by a certified sweep, especially for wood-burning units
• Asbestos and lead paint testing: relevant for any home built before 1980; lab samples ~$25-100 each
• Soil / geology: hillside or coastal homes
• Anything behind walls or under flooring: requires invasive testing, not in standard scope

Recommendations by property type

Older homes (pre-1980)

Always order: sewer scope, radon test, lead paint testing if you have young kids or plan to renovate, asbestos testing if you plan to disturb old materials. Budget extra time on the inspection — old homes have more to find.

New construction

Yes, you still need an inspection. Maybe even more so — punch-list defects, code shortcuts, and missed details are common with rushed production builders. Get inspections at pre-drywall ($300-500) and final ($400-700) if your builder allows it. See the new construction guide for the full process.

Rural homes

Always order: septic inspection, well water test (potability and flow rate), propane tank inspection if applicable. Budget for a longer visit — rural homes often have outbuildings, generators, and well/septic systems that aren’t in a city inspector’s default scope.

Coastal homes

Get a wind mitigation report ($75-150). It documents hurricane-resistant features (impact windows, roof straps, gable bracing) and can save 15-40% on homeowners insurance in FL, the Gulf Coast, and the Carolinas.

Condos and townhouses

Still get an inspection of your unit’s interior. The HOA covers common elements but the interior of your unit is yours — plumbing, electrical, HVAC, finishes. Also request the HOA’s recent reserve study and last 2 years of meeting minutes for systemic issues like pending special assessments.

HOA properties

Same as condos plus: read the CC&Rs carefully and review the HOA’s budget. Use the HOA Analysis tool to evaluate dues vs reserves health.

Inspection vs walk-through

These get confused constantly:

• The contingency inspection is the one this guide covers — happens within the inspection period after going under contract, drives negotiation, can let you walk.
• The final walk-through happens 24-48 hours before closing. It’s YOU (not an inspector) verifying the property is in the same condition it was, agreed-upon repairs were made, and the seller’s stuff is gone. It is not another inspection and it is not a do-over for issues you missed.

Some buyers also order an informational-only / pre-listing inspection before listing or in a no-contingency offer situation — same scope, but the goal is to know what you’re buying, not to negotiate.

Attending the inspection

Yes. Always attend. You’ll learn more in 2-3 hours of walking through with the inspector than from reading 50 pages of report afterward. Show up at the start, give the inspector space to work, and join them at each major system to ask questions. Good questions:

• “What would you do first if you owned this?”
• “What’s likely to fail in the next 5 years?”
• “What’s the cost range to fix this?”
• “What would you specifically follow up with a specialist on?”

Bring a notebook. Take photos.

Reading the report

A typical report is 30-80 pages with photos and notes for each issue. Most inspectors use severity tags like:

• Safety — immediate hazard (exposed wiring, gas leak, no GFCI in wet areas)
• Repair — needs work, often soon (active leak, failing water heater, broken seal)
• Monitor — not currently failing but watch (small foundation crack, aging roof)
• Improvement — not a defect, just suggested upgrade

Cost estimates in inspection reports are rough. Always get bid quotes from real contractors before negotiating major items.

Using the report to negotiate

You generally have a defined inspection period (5-15 days, set in your contract) to either accept the property as-is, request repairs or credits, or terminate. The strategy:

• Lead with safety items. “We need this rewired” lands better than “the doorknob is loose.”
• Bundle nitpicks into one number. Don’t hand the seller a 47-item list. Group them.
• Get bid quotes for major items ($1,000+). A roofer’s written estimate of “$8,500 to replace” anchors the negotiation far better than the inspector’s “$5,000-12,000”.
• Prefer credit at closing > price reduction > seller does the work. Credits give you the cash to fix it your way. Sellers cutting corners on last-minute repairs is a common regret.
• Know what’s reasonable to ask for. Major systems and safety: yes. Cosmetic and “deferred maintenance” you knew about going in: no — you priced for that.

The Inspection Negotiation calculator helps model credit vs price reduction trade-offs and what your monthly payment looks like under each.

Common mistakes

• Skipping the inspection in a hot market. Waiving inspection has cost buyers $20,000-100,000+ in undiscovered issues. If you must shorten the period, at least keep it.
• Not attending the inspection. You’ll learn 10x more in person than from the PDF.
• Using the inspector recommended by the listing agent. Conflict of interest. Find your own through your buyer’s agent or ASHI/InterNACHI’s search.
• Skipping the sewer scope on a pre-1980 home. $200 to potentially catch a $15,000 problem.
• Not getting bid quotes before negotiating. “About $5k” is a weaker ask than a written contractor estimate.
• Asking the seller to fix everything. They’ll either say no or do the cheapest possible job. Take the credit instead.
• Trying to negotiate on cosmetic items. Ages the relationship with the seller and rarely yields meaningful credits.

Tools you’ll use

• Inspection Negotiation — credit vs price model
• Closing Cost Estimator — where inspection fees fit
• HOA Analysis — for condos and townhomes
• Mortgage Calculator — recalculate after price negotiation
• Property Type Impact — if you’re comparing property types

For the broader buying arc, see the first-time buyer guide.