What Your Home Inspection Didn't Tell You
What a home inspection misses: what InterNACHI and ASHI standards exclude, plus sewer scope, radon, termite and regional checks. Rules vary by state.
In this article
Quick answer: A standard home inspection is a visual check of the parts of a house an inspector can readily see and reach. Under both the InterNACHI and ASHI standards, inspectors are not required to find radon, mold or wood-destroying insects, estimate how long systems will last, or check code compliance, and ASHI also excludes underground drainage and pools. Specialists cover those gaps, and which ones you need depends on your home and your region.
What a standard inspection covers
The two main US standards describe the same basic job. InterNACHI's Standards of Practice (last revised October 2022) have inspectors examine the roof covering, gutters and flashing, exterior, foundation and structure, heating and cooling, plumbing, electrical, and accessible fireplace components. ASHI's Standard of Practice says inspections cover the "readily accessible, visually observable, installed systems and components" and are "not technically exhaustive."
In practice that means:
- The inspector reports what is visible and accessible on the day.
- They operate systems with normal controls but do not dismantle anything or open walls.
- They flag symptoms, not causes, and usually refer you to a specialist when something looks serious.
What inspectors are not required to do
Both standards carve out major items. Inspectors are not required to do the following (where a line applies to only one standard, it is marked):
- Determine remaining life or life expectancy of systems
- Check compliance with current or past codes
- Identify mold, radon, other environmental hazards, or wood-destroying insects and organisms
- Inspect underground drainage and sewer lines, wells, cisterns or underground tanks (ASHI)
- Inspect swimming pools, spas and hot tubs (ASHI)
- Inspect the inside of flues and chimneys that are not readily accessible (ASHI)
- Provide engineering services or warranties (InterNACHI), or repair cost estimates
Your inspection agreement may add or remove items, so read it. Many inspectors offer some of these as add-on services or can refer you to a specialist.
Specialist inspections to consider
| Specialist | What it checks | When to consider it |
|---|---|---|
| Sewer scope | A camera run through the main drain line to the street or septic tank | Any home on a sewer line, especially older ones |
| Radon test | Radon gas in indoor air | Every home, per the EPA |
| Termite / wood-destroying insect (WDI) | Visible evidence of termites and other insects, and damage | Anywhere termites occur; some lenders require it |
| Mold and moisture | Water intrusion, humidity, hidden leaks | Musty smell, past leaks, visible staining |
| Chimney (Level 2) | Flue interior, usually with a camera | Any wood-burning fireplace or stove |
| Pool and spa | Equipment, safety features, structure | Any home with a pool |
| Septic or well | Tank, drain field, water quality | Any home not on city sewer or water |
| Structural engineer | Cause and fix for foundation movement | Cracks, sloping floors, sticking doors |
| Roofer, electrician, HVAC technician | Condition, age and remaining life | Anything the inspector flagged or could not judge |
Sewer line
Roots, breaks and sagging sections of the line between the house and the street are hard to see without a camera. A national HomeAdvisor survey (updated June 2026) lists a typical range of $271 to $1,725 for a sewer camera inspection, with big differences between cities. Ask whether the scope includes a recording you can keep, and whether the city or the homeowner is responsible for the section under the street.
Radon
Radon is a naturally occurring radioactive gas, and the EPA estimates it causes about 21,000 lung cancer deaths a year in the US. The EPA says nearly 1 in 15 US homes has elevated levels, recommends fixing a home at 4 pCi/L or higher, and suggests considering a fix between 2 and 4. For a sale, use a short-term test of at least 48 hours with the home closed up, and hire a qualified tester. Many states require radon professionals to be licensed or certified.
Mold
The EPA says that if visible mold is present, sampling is usually unnecessary, and there are no federal limits for mold spores. Focus on finding and fixing the moisture source, such as a roof or plumbing leak, poor drainage or high indoor humidity.
Termites and wood-destroying insects
The standard wood-destroying insect report in the pest-control industry (NPMA-33) documents only visible evidence in accessible areas, and it states it is not a guarantee against future infestation. The form is commonly used on HUD- and VA-backed loans, and some other lenders require it too.
Chimney and fireplace
The US Fire Administration advises having heating equipment and chimneys cleaned and inspected every year by a professional. A Level 2 inspection goes beyond a visual check and typically includes a camera scan of the flue. Some municipalities, such as Middletown Township in Pennsylvania, require a Level 2 inspection at resale.
Pool
Inspectors are not required to evaluate pools. The Consumer Product Safety Commission (CPSC) runs Pool Safely, which tracks drain cover and barrier safety, so ask a pool professional to check equipment and safety features.
Common gaps in a standard report
- Roof life left. Inspectors describe condition, but remaining life is outside the standard. Ask the seller for the roof's age and material, then see the roof lifespan guide.
- HVAC and other equipment age. A unit that runs on inspection day may still be near the end of its life. Ask a technician to check age, condition and efficiency.
- Polybutylene pipe. This gray plastic water supply pipe was made from 1978 to mid-1995 and went into roughly 10 million US homes. InterNACHI notes inspectors are not required to identify it or test it.
- Attic insulation and ventilation. ENERGY STAR recommends about R-30 to R-60 for an uninsulated attic, depending on climate zone. Measure depth yourself or ask an energy auditor.
- Problem drywall. CPSC received complaints from 44 states, mostly about homes built in 2006 and 2007, with sulfur smells and corroded metal.
How this varies by state and region
Climate, soil and local rules decide which extra checks pay off. Ask your local inspector, building department and insurer what is common nearby.
| Concern | Where it matters most | What to do |
|---|---|---|
| Radon | Can occur in any state; the EPA publishes radon zone maps | Test every home, and contact your state radon office |
| Wildfire | Fire-prone and wildland-edge areas | See IBHS wildfire research and NFPA guidance on ember-resistant details and the 5-foot "Zone 0" around the house |
| Hail and wind | Plains and Midwest states such as Texas, Oklahoma, Kansas and Nebraska, where wind/hail deductibles are common | Check roof age and impact resistance; read your policy's deductible |
| Expansive soil and foundation | Found in every state, per USGS mapping, but swelling potential varies by region | Hire a structural engineer for cracks or sticking doors |
| Freeze, ice dams, insulation | Cold-climate states | Check attic insulation and ventilation |
| Termites and moisture | More often a concern in warm, humid regions | Get a WDI report and check drainage and crawl spaces |
State licensing also varies. ASHI has put the number of states that license or register inspectors at about 35, with the rest unregulated. Texas licenses inspectors through the Texas Real Estate Commission and requires a standard report form. Illinois licenses them through its financial and professional regulation department. California does not license home inspectors at all. Check your state's licensing board before you hire, and ask which standard the inspector follows.
After the inspection
- Read the whole report, not just the summary.
- Sort findings into safety, major systems and cosmetic.
- Book specialists before your inspection or due-diligence deadline expires.
- Ask for repairs, credits or a price change where the contract allows.
- Keep the report, specialist reports and receipts in one place.
Steadwell can help after closing. You can store the report in the home document vault, turn each "monitor" item into a reminder in the home maintenance tracker, and on Plus run an AI condition assessment from photos. That assessment is not a substitute for a licensed inspector. For the first weeks in the house, see the new homeowner checklist.
Frequently asked questions
Does a home inspection check for mold, radon or termites?
Generally not. Both InterNACHI's and ASHI's standards say inspectors are not required to identify mold, radon or wood-destroying insects. Separate testing or a specialist covers each one.
Is a sewer scope worth it?
A standard inspection does not include underground sewer lines, and the line can be costly to repair. HomeAdvisor lists a typical range of $271 to $1,725 depending on where you live.
What if the inspector missed something that was visible?
Review your inspection contract and the standard it follows, and raise it with the inspector in writing. Rules and remedies vary by state, so contact your state licensing board or an attorney for advice.
Do all states license home inspectors?
No. Many do, with their own rules, and some do not. Look up your state's licensing board and ask the inspector which standard they follow.
Which specialists do I need for my area?
Radon testing applies nearly everywhere. Wildfire hardening, hail-resistant roofing and foundation or soil checks depend on your region, so ask local inspectors, your insurer and your building department.