Insulation and air sealing for Wildwood homes: attics, crawl spaces, rim joists and walls, starting with a free assessment of the R-value you actually have. The typical home here dates to the early-1990s, and 2% of its 13,391 homes went up before 1940.
Wildwood runs to about 67 square miles and roughly 35,417 people. It sits about 25 miles west of downtown St. Louis. Around 13,391 housing units sit inside those boundaries. The community dates back to 1995. We cover ZIP codes 63038, 63040, 63005, 63011, 63021, 63025 and 63069.
No completed job in Wildwood is logged in our records yet, and this page will say so until one is.
The typical home in Wildwood dates to around the early-1990s. Houses of this vintage usually got batts or blown fiber at whatever the standard of the day was, which is well short of what is recommended now. Most are one top-up away from being right.
Wildwood incorporated in 1995 by consolidating eleven historic unincorporated hamlets (Melrose, Hollow, Orrville, Westland Acres, Kelpe, Monarch, Glencoe, Pond, Fox Creek, Grover, Centaur — per the Wildwood Historical Society), so its housing mixes large-lot newer subdivisions with older pockets in those former hamlets.
We work across Wildwood rather than one corner of it — Melrose, Hollow, Orrville, Westland Acres, Kelpe, Monarch, Glencoe, Pond, Fox Creek and Grover included. Construction and vintage change between them, sometimes by thirty years and a whole different framing method, which decides whether a wall can be dense-packed at all.
The Big Chief Restaurant, a remnant of a 1928 Route 66 tourist complex, was added to the National Register of Historic Places in 2003, but it is an individual listing rather than a district.
The Census Bureau estimates 13,391 homes in Wildwood. 273 of them (2%) went up before 1940 — 28th of 44 places on this site for pre-1940 housing. The 1990s were the busiest decade, adding 5,087 of today's homes (38%); 15% predate 1980 and 19% were built in 2000 or later. For St. Louis County as a whole the pre-1940 share is 10%, so Wildwood sits below it.
Of 12,851 occupied homes, 64% heat with utility gas and 31% with electricity; another 4% burn propane or other tank gas. Electric heat here is more common than across the county (23%), and ranks 25th of 44 on this site. Whoever comes out will ask about the furnace or heat pump first, since the heating fuel and the utility named on the bill settle which program money is on the table.
92% of occupied homes are owner-occupied and 92% of all homes are single-family detached houses. With houses like these, the conversations we expect most are about an energy assessment before deciding what to fix first.
| Built | Homes | Share | |
|---|---|---|---|
| Before 1940 | 273 | 2% | |
| 1940s | 185 | 1% | |
| 1950s | 215 | 2% | |
| 1960s | 237 | 2% | |
| 1970s | 1,151 | 9% | |
| 1980s | 3,677 | 27% | |
| 1990s | 5,087 | 38% | |
| 2000s | 1,823 | 14% | |
| 2010s | 680 | 5% | |
| 2020 or later | 63 | 0% |
13,391 homes, Census ACS 2020–2024 (B25034, B25040, B25003); 12,851 occupied.
8,764 of Wildwood's 13,391 homes (65%) were built in the 1980s and 1990s. The gaps in houses of that age are the parts nobody sealed: batts stuffed into the rim joist, bare spots over cathedral and tray ceilings, soffit vents buried with no baffles, can lights punched through the ceiling plane. A top-up plus a day of sealing usually covers it.
Wildwood does not publish the energy code edition it enforces, so this page does not name one. Wildwood does not adopt model codes directly. Chapter 500 of its code adopts St. Louis County's code chapters by reference: Section 500.035 adopts the Residential Code, Chapter 1116, SLCRO 27,654, approved December 18, 2019 and adopted effective April 1, 2020, as amended, most recently touched by Ordinance No. 2908 of August 12, 2024 and Ordinance No. 2958 of January 13, 2025. The chapter has sections for building, residential, existing building, electrical, plumbing, mechanical, property maintenance and explosives codes, but no energy conservation code section, and the word 'energy' does not appear in the chapter. The State of Missouri's building-codes-by-city list lists Wildwood as 2015 IECC, 2015 IRC and 2015 IBC. Across this metro the adopted editions run from the 2015 IECC to the 2024 IECC, and several jurisdictions have no energy code at all, which is a wide spread. Ask which one your contractor is building to.
Wildwood's Planning Department directs residents to the St. Louis County Department of Public Works, Division of Code Enforcement document 'Work That Does Not Require a Building Permit,' which it hosts on the city website. Item 35 of that list exempts increasing attic insulation and installing exterior wall insulation under new or replacement siding. The same item states that a building permit is required to install insulation, furring strips and drywall on the room side or the interior basement side of exterior walls. Air sealing, caulking and weatherstripping are not named.
The city's building permit page says nothing about contractor licensing or registration. Section 500.010 of the city code authorizes the Mayor to sign an agreement with St. Louis County covering permits, inspections, licensing and approval of plans, so licensing appears to run through the county, but no page states what an insulation contractor must hold.
The published number is 636-458-0440. The department page is here.
Permitting is on us, not on you.
Wildwood is on the Missouri side, where most addresses buy their electricity from Ameren Missouri. Its Pay As You Save program publishes $0.20 per square foot on ceiling and attic insulation and $0.06 per square foot on air sealing for the 2026 program year; the incentive comes off the cost and the rest is repaid through a monthly charge on the bill. The conditions: an attic going from R-20 or below to at least R-38, air sealing that cuts measured leakage by 20 percent, and twelve months in the home. CommunitySavers can include attic insulation at no charge for income-eligible households. Income-qualified households can apply to Community Action Agency of St. Louis County (CAASTLC) (314-863-0015) for free weatherization instead. For every condition attached, see the St. Louis County page or the rebate guide.
Every layer of an insulated attic, explained
Wildwood borders Chesterfield, Clarkson Valley, Ellisville, Eureka, Pacific and Franklin County. 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. Across the 7 places in this table there are 3 different adopted editions (2015 IECC, 2015 IRC ch. 11 and 2018 IRC ch. 11), and 2 of the 7 publish a permit rule for insulation.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| Wildwood | Not published | — | Not for an attic top-up | 636-458-0440 |
| Chesterfield | Not published | — | Not published | 636-537-4000 |
| Ellisville | 2015 IRC ch. 11 | R-49 | Not published | 636-227-9660 |
| Eureka | 2018 IRC ch. 11 | R-49 | Not published | 636-938-5233 |
| Pacific | None adopted | — | Not published | 636-271-0500 |
| Affton | 2015 IECC | R-49 | Not for an attic top-up | 314-615-5184 |
| Ballwin | Not published | — | Not published | 636-227-2129 |
All 21 St. Louis County jurisdictions side by side →
Wildwood does not publish the energy code edition it enforces, so we do not state a required figure here. The Department of Energy recommends R60 for an uninsulated attic in this climate zone and R49 where there are already a few inches.
Wildwood's Planning Department directs residents to the St. Louis County Department of Public Works, Division of Code Enforcement document 'Work That Does Not Require a Building Permit,' which it hosts on the city website. Item 35 of that list exempts increasing attic insulation and installing exterior wall insulation under new or replacement siding. The same item states that a building permit is required to install insulation, furring strips and drywall on the room side or the interior basement side of exterior walls. Air sealing, caulking and weatherstripping are not named.
Ameren Missouri's Pay As You Save: $0.20 per square foot for an attic starting at R-20 or below and $0.06 per square foot for air sealing in 2026, with the balance on the electric bill. The federal 25C credit ended for work placed in service after December 31, 2025.
The typical home in Wildwood dates to around the early-1990s; the Census Bureau's 2020-2024 median year built is 1992. Of its 13,391 homes, 2% went up before 1940 and 19% in 2000 or later. It is a median for the place, not a survey of individual houses.
Code and permit facts checked September 10, 2026, rebates October 24, 2026; housing: Census ACS 2020–2024. Sources: ecode360.com (2) · cityofwildwood.com (2, 3) · data.mo.gov · en.wikipedia.org · wildwoodhistoricalsociety.org · city-data.com · ameren.com (2, 3, 4) · energystar.gov · data.census.gov. These change; confirm with the building department at 636-458-0440 or your electric utility first.
Free assessment, a measured R-value, and photos you keep either way.
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