New Construction Buyer's Guide for Iowa

New construction in Iowa still needs an independent inspection. A municipal building inspector checks code compliance on a schedule at a handful of milestones; that is a different job from walking a finished house looking for what was done wrong, left out, or damaged after the last official visit. No Iowa law requires a home inspection before a sale (the one mandatory time-of-transfer inspection covers private septic systems), and a certificate of occupancy is not a quality warranty. Add to that the specific Iowa realities — a Zone 1 radon state statewide, frost protection set locally rather than by a single state number, fresh backfill on a graded lot that has not yet settled — and there is plenty for an independent set of eyes to find.

Why inspect a brand-new house in Iowa?

Because code compliance and construction quality are not the same thing, and because nobody on the project is working for you. The municipal inspector verifies compliance at defined milestones against the adopted code, on a limited schedule, across many houses. The builder's superintendent is managing a schedule and subcontractors. The subcontractors are paid to finish and move on. An independent inspector is the only person on site whose only obligation is to the buyer.

What we find on new Iowa homes is rarely dramatic and frequently expensive later: missing or compressed attic insulation at the eaves, bath fans terminating in the attic instead of outdoors, kinked or disconnected flex duct, missing kickout flashing at roof-wall intersections, gaps in exterior air sealing, reversed polarity and missing GFCI or AFCI protection, plumbing that drains slowly because a line was set at the wrong pitch, unsealed penetrations through the slab and rim joist, and grading that slopes toward the house instead of away.

Iowa has no statewide requirement that any home be inspected at the time of sale, new or otherwise, and a certificate of occupancy documents that the jurisdiction's process was completed — not that the workmanship is good. Builders generally welcome a competent independent inspection; a reputable one would rather fix an item before closing than field a warranty call in February.

When should you inspect during an Iowa build?

There are three useful points, and the more of them you use the better the outcome. A pre-drywall inspection, after framing, rough electrical, rough plumbing and rough HVAC are complete but before insulation and drywall go up, is the single highest-value one. Everything structural and everything mechanical is visible exactly once in the life of the house, and that is the moment. We look at framing, notching and boring of structural members, joist hangers, fire blocking, duct routing and support, plumbing slope and venting, and whether the window and door flashing was installed in the right sequence.

A final inspection before closing covers the finished house: all systems operated, every fixture and appliance run, grading and drainage checked, the roof and attic evaluated, and the punch list documented with photographs while you still have closing as leverage.

The eleven-month inspection, done before a typical one-year builder warranty expires, is the one buyers most often forget. A house has been through a full Iowa cycle by then — a heating season, a freeze-thaw spring, a humid summer — and defects that were invisible at closing have surfaced. Drywall cracks, doors that stick, settled backfill, grading that no longer sheds water, and HVAC problems that only show at temperature extremes all appear in that first year. Warranty terms vary by builder; read yours and calendar the deadline.

Do new Iowa homes need a radon test?

Yes. Radon comes from the soil, and the entire state of Iowa is EPA Radon Zone 1 — every county, regardless of the age of the houses on it. Iowa HHS reports that the Iowa Radon Survey found Iowa has the largest percentage of homes above the EPA action level of 4 pCi/L of any state, at 71.6 percent. A house finished last month sits on the same ground as the one next door.

Many newer Iowa homes are built with passive radon-resistant features: a layer of gas-permeable aggregate under the slab, a sealed membrane over it, and a capped vent pipe routed from beneath the foundation up through the roofline. If your home has that, find the pipe — it is usually visible in a mechanical room or closet. It is a genuine benefit, because converting it to an active system later is straightforward work.

But a passive stub is not a solution, and this is where new-construction buyers most often get it wrong. Passive venting depends on natural air movement, which is weakest exactly during the Iowa heating season when radon levels run highest. New homes with the rough-in in place still test above the action level regularly. The only thing that tells you your number is a measurement. Test the finished house under closed-house conditions, and if the result is at or above 4.0 pCi/L, adding an inline fan to the existing pipe is usually all it takes — then re-test to confirm.

What should you check about grading and drainage on a new Iowa lot?

New lots are the most likely place in Iowa to find a drainage problem, because the soil around the foundation was excavated, replaced and mechanically compacted only months ago and has not finished settling. Backfill settles for years. Grading that looked correct at final grade often develops a reverse slope toward the foundation by the first or second spring, and that is exactly what the eleven-month inspection is for.

Region matters. On the Southern Iowa Drift Plain, where the Iowa Geological Survey describes a loess mantle typically five to thirty feet thick over old pre-Illinoian drift on a deeply dissected landscape, lots slope and shrink-swell soil moves seasonally — so the questions are where the water goes on the way down and whether the walkout side drains. On the Des Moines Lobe in north-central Iowa the last glaciation was recent in geological terms and the landscape is flat and poorly drained, which is why so much of it is tiled; there the questions are sump capacity, discharge routing, and whether stormwater has anywhere to go at all.

On any new Iowa lot, check that grade falls away from the foundation on every side, that downspouts discharge well clear of the backfill rather than onto it, that window wells have working drainage, that the sump discharges far enough away not to recirculate, and that the neighbors' finished grade does not send their runoff to you.

How does frost depth work on Iowa foundations?

Frost protection depth in Iowa is set locally, not statewide. The IRC requires footings to extend below the frost line specified in Table R301.2, and that table is a blank the adopting jurisdiction fills in. Iowa's building code explicitly declines to set a single number: 481 IAC 301.8(3) notes that the values for Table R301.2 are determined by the location of the project. There is no authoritative statewide Iowa residential frost depth, and anyone quoting you one is guessing.

Note the agency number as well. Iowa's building code chapters moved from agency 661 to agency 481 — the Department of Inspections, Appeals and Licensing — effective November 26, 2025. Citations to 661 are outdated.

For a buyer, what this means practically is that the correct footing depth for your address is a question for the local building department, and it is a reasonable one to ask. What an inspector can do is look for the evidence frost movement leaves behind: seasonal cracking that opens and closes, heaved stoops, garage slabs and porch piers, doors that stick only in winter, and movement at the shallowest foundation elements — which on a new house are usually the porch, the stoop and the deck footings rather than the house itself. Manufactured housing is a separate regime: 481 IAC chapter 322 defines a frost-protected footing as foundation material installed to a depth of 42 inches below finished grade and requires ground anchors to reach below that depth.

New construction FAQs for Iowa buyers

Will the builder let me bring my own inspector? Almost always, and a builder who refuses has told you something useful. Some builders ask for scheduling coordination or require the inspector to carry insurance, which is reasonable. Get the arrangement in writing early rather than the week before drywall.

Is the municipal inspection enough? No. It verifies compliance with the adopted code at defined milestones. It is not a walkthrough of workmanship on your behalf, and it does not cover items that are outside code but still defects.

Does a certificate of occupancy mean the house is finished correctly? It means the jurisdiction's process was completed. It is not a warranty and not a quality assessment.

What if the home is a new townhome or condominium? The unit gets inspected; the association's common elements generally do not — standard practice excludes common elements and common areas in multi-unit housing. Read the governing documents; Iowa's condominium statute is Iowa Code chapter 499B.

When exactly does the warranty run out? Warranty terms vary by builder and by component, and some coverages are shorter than others. Read your specific warranty document and put the deadline on a calendar the day you close, then schedule the eleven-month inspection with room to submit a claim.