What a Home Inspection Does Not Cover: Six Things

The plumbing checklist that governs a general home inspection across most of the country tells the inspector to inspect "sewage ejectors, sump pumps and related piping" — item 6.1.A.6 of ASHI's national standard in the edition currently in force, 7.1.A.6 in the revision waiting behind it. Further down the same section, in the list of what that inspector is not required to inspect, sits "septic and other sewage disposal or wastewater treatment systems." Texas draws the identical line with different words: not required to check "for sewer clean-outs" or "for the presence or performance of private sewage disposal systems." The pump inside the house is in scope. The pipe leaving it is not. Nothing on a finished report says that in those words — the closest it comes is a clause on the general limitations page, which nobody reads on the day they are deciding whether to waive the option period.

That gap is not a mistake by that inspector. It's the standard working exactly as written. Every general home inspection performed in the United States is built on one of a small number of governing documents — a state's licensing rule, where one exists, or a private trade association's Standard of Practice, adopted by reference in the inspection agreement where it doesn't — and every one of those documents draws the boundary in almost the same place. Texas is unusual only in that its version is a numbered state regulation you can pull up and cite by section. Compare it against the American Society of Home Inspectors' national model, which governs inspections in states with no licensing law at all, and the two lists of exclusions line up so closely they're worth reading side by side.

Both documents were read in full on 19 August 2026 and the section numbers below re-checked on 20 August 2026. Texas's rule is 22 TAC §§535.227–535.233, the Texas Real Estate Commission's own pocket edition, adopted effective September 7, 2016 and current as of this reading. ASHI's currently effective standard is the version effective March 1, 2014; a renumbered 2026 revision was approved by ASHI's membership on January 8, 2026 but, per ASHI's own resource page, is "not yet effective" as of this reading — the 2014 text is still the one that governs. Where the two versions differ, both are cited below.

What "inspect" is defined to mean before anyone books an appointment

Neither standard promises a diagnosis. Both promise a look.

Texas's rule defines a real estate inspection as "a limited visual survey and basic performance evaluation of the systems and components of a building using normal controls that provides information regarding the general condition of a residence at the time of inspection" — and adds, in the next clause, that it "is not intended to be a comprehensive investigation or exploratory probe to determine the cause or effect of deficiencies" (22 TAC 535.227(a)(3)). ASHI's language is different but lands in the same place: the inspector shall "inspect the readily accessible, visually observable, installed systems and components specified in this Standard," and the standard "is NOT technically exhaustive" (Sections 2.4.A and 15.1.B.1 of ASHI's 2026 text; 2.2.A and 13.1.B.1 of the currently effective 2014 text).

The banned-equipment lists make the point harder to miss than the scope language does. Texas names, item by item, what the inspector does not have to bring: thermal imaging equipment, moisture meters, gas or carbon monoxide detectors, environmental testing equipment, elevation determination devices, and ladders capable of reaching anything over one story up (22 TAC 535.227(a)(3)(C)(i)). ASHI's 2026 revision adds a new stand-alone section on the same subject, and its list is close enough to Texas's to have been copied from it: amp meters, pressure gauges, moisture meters, combustible-gas or carbon-monoxide detectors, thermal imaging, environmental testing equipment, elevation devices, ladders over one story — plus two items Texas doesn't name because they weren't common when its rule was drafted: cameras built to inspect the interior of a drain or sewer line, and drones (Section 16.2.A). A walk-through with a flashlight and a voltage tester is what both documents are actually describing.

The six things this inspection is written not to reach

Four of the six below become their own paid, separately licensed inspections — the subject of the companion piece on which specialist inspections to order. The other two are not something you can pay anyone to fix, because no inspector, general or specialist, is asked to answer them.

The septic system and the sewer line. Nothing in the core plumbing section touches either one. Texas says outright that the inspector is not required to check "for sewer clean-outs; or for the presence or performance of private sewage disposal systems" (535.231(a)(2)(D)(iv)–(v)). Septic only enters the picture as a paid optional module, and even that module doesn't excavate the drain field, size the tank, or determine what kind of system is buried out there (535.233(g)(2)). ASHI doesn't offer an optional module for it at all — "septic and other sewage disposal or wastewater treatment systems" is simply excluded, full stop, in both its current and pending text (6.2.A.7 in the 2014 edition, 7.2.A.7 in the 2026 one). That exclusion sits directly beneath the clause that puts sewage ejectors and sump pumps inside the inspection, which is how a report can carry a clean plumbing section and still have said nothing at all about the buried lateral.

Wood-destroying insects and organisms. Texas's rule states it in one clause: the inspector is not required to determine "the presence or absence of pests, termites, or other wood-destroying insects or organisms" (535.227(d)(3)(A)). ASHI's wording is close enough to be functionally identical. In Texas that report comes from a Structural Pest Control license, a different category from a real estate inspector entirely, and some lenders won't clear a loan without it sitting in the file as its own document.

Environmental hazards. Asbestos, lead-based paint, mold and mildew, and — in Texas's phrasing — "any other environmental hazard, environmental pathogen, carcinogen, toxin, mycotoxin, pollutant, fungal presence or activity, or poison" (535.227(d)(3)(B)). ASHI's currently effective language covers "allergens, toxins, carcinogens, electromagnetic radiation, noise, radioactive substances, and contaminants in building materials, soil, water, and air"; its pending 2026 text keeps that list and folds mold and fungus into the same clause explicitly. Radon isn't named by Texas at all — it's caught only by the general environmental-hazard clause — which is exactly why it needs its own line item and its own test kit rather than a mention on a walk-through report.

The chimney's flue interior and draft. This one is carved out even though the fireplace itself is squarely inside the core inspection. Texas: the inspector is not required to "verify the integrity of the flue," "perform a chimney smoke test," or "determine the adequacy of the draft" (535.228(i)(2)). ASHI's pending 2026 text is the most direct of any clause in either document — it says the inspector need not "perform any type of chimney inspection, such as a National Fire Protection Association (NFPA) 211 Level I, II or III inspection," naming the actual standard a chimney specialist would work from (Section 13.2.E). That's not a gap in the general inspection. It's a pointer to a different, named profession.

Private water wells and water quality. A well only shows up in the report at all as a paid optional item, and Texas's optional-well provision limits the inspector to operating fixtures and recommending — not performing — coliform testing (535.233(f)). Water quality and potability are excluded outright even where the optional add-on is purchased (535.231(a)(2)(E)(i)). ASHI's language matches: wells, well pumps, and water-quality determinations are both on the not-required list in current and pending text alike.

Why a deficiency happened, and how long the fix will hold. This is the one nothing on the market fixes by hiring a different kind of inspector, because it isn't an inspection question. Texas: the inspector is not required to "anticipate future events or conditions" — decay, deterioration, or damage that may occur after the inspection — nor to determine "the cause or effect of deficiencies" (535.227(d)(4), (d)(3)(E)). ASHI: "the causes of any condition or deficiency," "future conditions... including the failure of systems and components," and "the age, life expectancy or remaining useful life of systems and components" are all listed exclusions (Sections 15.2.A.4, 15.2.A.2, 15.2.A.19 in the 2026 text). Both documents then hand the actual answer to someone else — Texas's inspector "is not required to recommend or provide engineering... services" (535.227(d)(7)); ASHI's inspector is not required to "perform architectural, engineering... services or to confirm or to evaluate such services performed by others" (Section 15.2.B.2). A crack in a foundation wall can be reported. Why it opened, and whether it will open further, is an engineer's question, not an inspector's.

Texas parks the septic and well items in a section headed "Optional Components or Systems," alongside landscape irrigation, swimming pools and spas, and outbuildings (535.233). That heading is what pushes those items onto a Texas quote as separate lines rather than folding them into one number: 535.233(b) says that if the inspector agrees to look at anything under that heading at all, the general provisions and that item's own subsection both apply, which in practice means a separate line, a separate scope, and sometimes a separate signature on the agreement. If a property has a well or a septic system and neither shows up as its own line on the quote you were given before the inspection, that omission is worth a question before the inspector arrives, not after the report does.

What happens to this list where there's no licensing board at all

Texas is not typical. Most states either license inspectors under a rule that borrows heavily from ASHI's or InterNACHI's model — which is exactly why the Texas list above tracks the national one so closely — or don't license home inspectors as a distinct profession at all.

California is the clearer example of the second kind. There is no state agency issuing home inspector licenses and no numbered standard of practice written into the California Code. Instead, Business and Professions Code §7196 — added in 1996, effective January 1, 1997 — sets a single sentence of a duty: an unlicensed home inspector must conduct the inspection "with the degree of care that a reasonably prudent home inspector would exercise." Nothing in that sentence enumerates six things or sixteen. What decides the actual scope of your inspection in a state built this way isn't a regulation. It's the contract you sign before the inspector walks the property, which will typically adopt a private standard — ASHI's, InterNACHI's, or a state trade association's — by reference in a single clause. Read that clause before the inspection, not after, because it is doing the same job Texas's rule does by statute.

There's a third category between these two, and it catches more buyers off guard than either extreme. Some states require a license and a set number of training hours but leave the actual scope of the inspection to whichever private standard the inspector chooses to name in the contract, rather than writing exclusions into the licensing statute itself the way Texas does. In that kind of state the license tells you the person is allowed to work; it tells you nothing about which six things — or sixteen — they didn't look at. The contract still has to be read on its own, license or no license.

Reading your own report against this list

Every item above should show up on your own report as one of four things, if the standard behind it was followed. The inspector "shall indicate, by checking the appropriate boxes on the form, whether each item was inspected, not inspected, not present, or deficient and explain the findings in the corresponding section in the body of the report form" — 22 TAC §535.223(5), read 20 August 2026, which also now requires an explanation when multiple boxes are checked on one item. Worth noting if you are working from the TREC booklet linked above: it still names Form REI 7-5, while the rule in force adopts Form REI 7-6. ASHI's version of the same requirement is written as an obligation rather than a form field: the report must state which systems and components "were present at the time of the home inspection but were not inspected and the reason(s) they were not inspected" (2.2.B.4 in the 2014 text, renumbered 2.4.B.5 in the 2026 revision).

That distinction is the one worth checking on your own copy before the option period runs out. A septic system marked "Not Present" means the inspector looked for evidence of one and found none — a real finding. The same system marked "Not Inspected" means nobody looked, which is what the standard expects by default for anything on the six-item list above unless you paid for the optional add-on or hired the specialist separately. Both documents require the inspector to say which one it was and why, under Texas's departure provision (535.227(f)) and ASHI's reporting section alike. If your copy doesn't say, that's the one question worth a phone call before the contingency clock on your own purchase contract runs out — because a deal that stalls later over a defect nobody flagged early is one of the more common ways a purchase falls apart in the final week rather than the first one.