University City enforces its own energy code edition, which sets its own attic number. Here is that number, whether the work needs a permit, which utility programme pays toward it, and what a house of this vintage usually turns up.
University City runs to about 5.9 square miles and roughly 35,065 people. It sits about 6 miles west of downtown St. Louis. Around 18,019 housing units sit inside those boundaries, most of them built before anyone measured a house for air leakage. The community dates back to 1906.
No completed job in University City is logged in our records yet, and this page will say so until one is.
The typical home in University City dates to around the mid-1940s. Houses built before the war generally went up with nothing in the walls at all and whatever went into the attic afterwards. Anything up there was added later, usually in a hurry.
The city's population peaked at 51,249 in 1960 and declined afterward. Its southern half retains streetcar-suburb-era architecture from the early 20th century along Delmar Boulevard, while post-WWII development dominates the northern sections.
That includes Delmar Loop. Housing age and construction shift across University City, sometimes by decades within a few streets, which is why we look in the attic before quoting rather than after.
Incorporated in 1906 by Edward Gardner Lewis. The Delmar Loop–Parkview Gardens Historic District (NRHP-listed 1984) covers 84 acres and 289 contributing buildings, construction of which began in 1911 in Bungalow/Craftsman, Tudor Revival, and Georgian Revival styles.
Housing of this age in University City was built before insulation was a line item. The walls are typically empty — brick with a furred-out plaster interior, or balloon-framed timber with cavities that run uninterrupted from the sill all the way to the attic, which is why the top floor of an old house here is cold in a way that no amount of attic fibre fixes on its own. Whatever is in the attic went in later, often over the tops of the joists and often over the top of everything else that had been up there first. We expect open chases behind knee walls, plaster-and-lath ceilings that leak air at every fixture, and balloon cavities that need blocking before anything is blown. Two things we look for before quoting a house this old: loose grey-brown flakes in the attic, and cloth-covered wiring on ceramic knobs.
University City enforces the 2018 IECC. University City's Energy Conservation Code article adopts the International Energy Conservation Code, 2018 Edition. The article traces to Ordinance No. 6937, Section 1, of October 28, 2013 and was amended to the 2018 edition by Ordinance No. 7139 of January 25, 2021. The amendments are administrative: they set the code's title and enforcing agency (C101), align third-party inspection procedures with the local building code (C105), address stop work order violations (C108) and route appeals through the local Building Code (C109). The city's residential code article adopts the International Residential Code, 2018 Edition, by Ordinance No. 6933, Section 1, of October 28, 2013 as amended by Ordinance No. 7139.
Under that edition the required attic value for new work here is R-49, and walls R-20, or R-13 cavity plus R-5 continuous. For comparison, the Department of Energy recommends R60 for an uninsulated attic in this climate zone and R49 where there are already a few inches up there.
2018 IECC Table R402.1.2, climate zone 4 (except marine), as reproduced in the U.S. Department of Energy / PNNL Building America Solution Center comparison of 2009-2021 IECC and IRC minimum insulation requirements.
Nothing University City publishes settles this. Its permit lists name the work types it cares about, and insulation is not among them in either direction. That is the normal state of affairs across this metro — only a handful of the 45 jurisdictions on this site say anything about it at all. Nothing on the pages that did load names insulation, air sealing or weatherization as requiring or not requiring a permit. So we ask the department directly before the first day on site, and whatever comes back, pulling it is our job rather than yours.
University City issues electrical permits only to electrical contractors licensed by St. Louis County, and tells residents they can verify a contractor's license by calling the Community Development Department. Nothing published states that an insulation contractor must be licensed or registered, with either the city or the county.
The department's own number was not published on an official source when this page was built, so we are not printing one. The department page is here.
Permitting is on us, not on you.
University City is on the Missouri side, which for most addresses means Ameren Missouri — and Ameren Missouri does not hand out a straight per-square-foot insulation rebate the way its Illinois sister utility does. What it runs instead is Pay As You Save: a free home energy assessment, then the work installed by a programme partner and paid back through a fixed monthly charge on the electric bill, which cannot exceed 80% of the estimated monthly saving, so the bill still comes down while it is being repaid. No loan and no credit check.
Published incentives inside that programme for the 2026 programme year are $0.20 per square foot on ceiling and attic insulation, $0.06 per square foot on air sealing, and 50% of costs up to $250 per home on duct sealing. Each one has a condition attached, and they matter:
Ameren Missouri also runs CommunitySavers, which installs attic insulation at no charge for income-eligible households. The program operates through December 31, 2026; incentives are dependent on available funds.
Spire, the gas utility on this side, lists furnace, water heater and thermostat rebates on its Missouri rebate page rather than a standalone insulation one. Its published route to attic insulation and air sealing is the same on-bill Pay As You Save programme, which it co-delivers, plus income-based weatherization. If you are a Spire customer it is worth ringing them to ask what is open this year, because that page moves.
If the household income qualifies, the work can be free rather than discounted. St. Louis County is served by Community Action Agency of St. Louis County (CAASTLC) under the Missouri low-income weatherization program — 314-863-0015, details here.
One more, by its absence: the federal 25C credit, which covered 30% of insulation and air sealing up to $1,200 a year, ended for anything placed in service after 31 December 2025. Work finished on or before that date is still claimed on that year's return; nothing done in 2026 is. It should not be in your 2026 price, whoever tells you otherwise — the rebate guide has the detail.
NOAA's 1991–2020 normals put 84.9 nights a year at or below freezing here, and only 19.3 days that never climb back above it. Most freezes in University City thaw the same day, and that daily cycling is what drives moisture into a cold attic. The energy code and rebate guide has the full climate figures.
University City borders St. Louis City, Olivette, Ladue and Northmoor. These are the ones we also cover, each with its own energy code and permit rule:
Elsewhere in St. Louis County we also cover:
Missouri sets none of this at state level, so the number that was right one municipality over is not automatically right here.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| Affton | 2015 IECC | R-49 | Not for an attic top-up | 314-615-5184 |
| Ballwin | Not published | — | Not published | 636-227-2129 |
| Brentwood | 2024 IECC | R-49 | Not published | 314-963-8602 |
| Chesterfield | Not published | — | Not published | 636-537-4000 |
| Clayton | 2021 IECC | R-60 | Not published | 314-290-8463 |
| Creve Coeur | 2015 IECC | R-49 | Not published | 314-872-2500 |
| Des Peres | 2018 IRC ch. 11 | R-49 | Not published | 314-835-6130 |
| Ellisville | 2015 IRC ch. 11 | R-49 | Not published | 636-227-9660 |
| Eureka | 2018 IRC ch. 11 | R-49 | Not published | 636-938-5233 |
| Florissant | 2021 IECC | R-60 | Not published | 314-839-7648 |
| Kirkwood | 2021 IECC | R-60 | Not published | 314-822-5823 |
| Manchester | Not published | — | Not published | 314-615-5184 |
| Maryland Heights | 2015 IECC | R-49 | Not published | 314-291-6550 |
| Mehlville | Not published | — | Not for an attic top-up | 314-615-5184 |
| Oakville | 2015 IECC | R-49 | Not for an attic top-up | 314-615-5184 |
| Richmond Heights | 2024 IECC | R-49 | Not published | 314-646-7658 |
| Unincorporated St. Louis County | 2015 IECC | R-49 | Not for an attic top-up | 314-615-5184 |
| Town and Country | 2018 IRC ch. 11 | R-49 | Not published | 314-587-2820 |
| Webster Groves | Not published | — | Not published | 314-963-5300 |
| Wildwood | Not published | — | Not for an attic top-up | 636-458-0440 |
Free assessment. We check for vermiculite and knob-and-tube before anything else, and tell you either way.
The code edition University City enforces sets R-49 for new work. The Department of Energy separately recommends R60 for an uninsulated attic in this climate zone, and R49 where a few inches are already there.
Unresolved on paper. University City names the work types it wants permits for and insulation is not one of them, but nor is it on the exemption list. It gets settled by phone before we schedule, at our end.
For most addresses here the route is Ameren Missouri's Pay As You Save programme, which publishes $0.20 per square foot on ceiling and attic insulation and $0.06 per square foot on air sealing for the 2026 programme year. Both carry conditions: the attic has to start at R-20 or below and reach at least R-38, and the air sealing has to cut leakage by at least 20 percent. The incentives sit inside tier 4 of the programme and need you to have lived in the home for the past twelve months, and they are recovered through a monthly charge on the electric bill rather than paid as a cheque. Income-eligible households can get attic insulation at no charge through CommunitySavers instead. The federal 25C credit ended for work placed in service after 31 December 2025.
The typical home in University City dates to around the mid-1940s. Houses built before the war generally went up with nothing in the walls at all and whatever went into the attic afterwards. Anything up there was added later, usually in a hurry. That figure is an ACS-derived median republished by housing-data services, not a survey of individual houses.
Not yet. We have no completed job logged in University City, and we would rather say so than put a number on this page that is not real.
Neither state licenses insulation contractors as a trade. In Missouri there is no statewide residential code at all, and registration is imposed city by city — several metro municipalities require a contractor to be registered with them before a permit is pulled. What matters more in practice is utility programme enrolment, because that is what decides whether your rebate is real.
Energy code, permit and department details for University City come from the jurisdiction's own published pages and codified ordinances. Rebate figures come from the utility's own published incentive tables and carry the programme year they were verified in. Housing-age figures are ACS-derived medians republished by housing-data services, so treat them as approximate. Sources: ecode360.com · ecode360.com · ucitymo.org · ucitymo.org · basc.pnnl.gov · ecode360.com · ecode360.com · ucitymo.org · en.wikipedia.org · en.wikipedia.org · city-data.com · ameren.com · ameren.com · ameren.com · ameren.com · energy.gov. Adopted code editions, department phone numbers and utility rebate amounts all change — confirm with the jurisdiction or the utility before relying on anything here.