Insulation in Ellisville, Missouri

Insulation and air sealing in Ellisville

Ellisville runs to about 4.4 square miles and roughly 10,002 people. It sits about 20 miles west of downtown St. Louis. Around 4,349 housing units sit inside those boundaries. The community dates back to 1932. We cover ZIP codes 63011, 63021 and 63038.

No completed job in Ellisville is logged in our records yet, and this page will say so until one is.

The housing stock in Ellisville

The typical home in Ellisville dates to around the early-1980s. 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.

Mostly 1970s-80s subdivisions (about 26% built in the 1970s, 17% in the 1980s).

Settled before 1837, Ellisville incorporated as a village in 1932 (to create its own school district) and became a fourth-class city in 1957; Money magazine ranked it #25 on its 2009 'Best Places to Live in America' list.

Ellisville homes in the Census numbers

The Census Bureau estimates 4,349 homes in Ellisville. 10 of them (0%) went up before 1940 — one of the five lowest pre-1940 shares among the 44 places on this site. The 1970s were the busiest decade, adding 1,120 of today's homes (26%); 45% predate 1980 and 23% were built in 2000 or later. For St. Louis County as a whole the pre-1940 share is 10%, so Ellisville sits below it.

Of 4,155 occupied homes, 64% heat with utility gas and 35% with electricity. Electric heat here is more common than across the county (23%), and ranks 18th of 44 on this site. That is why the assessment asks how the house is heated: the fuel and the name on the utility bill decide which program, if any, can pay toward the work.

75% of occupied homes are owner-occupied and 60% of all homes are single-family detached houses. On a housing mix like this, the likely starting points are an attic top-up over postwar fiberglass and an energy assessment before deciding what to fix first.

4,349 homes, Census ACS 2020–2024 (B25034, B25040, B25003); 4,155 occupied.

Sealing comes first in Ellisville

1,390 of Ellisville's 4,349 homes (32%) 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.

What the energy code requires in Ellisville

Ellisville enforces the 2015 IRC Chapter 11 (Energy Efficiency). Section 500.010 of the Ellisville code adopts twelve codes: the 2015 International Building Code, the 2015 International Residential Building Code for One- and Two-Family Dwellings, the 2015 National Green Building Standard, the 2015 International Plumbing Code, the 2015 International Property Maintenance Code, the St. Louis County explosives, weights and measures and property maintenance codes, the 2015 International Swimming Pool and Spa Code, the 2014 National Electrical Code, the 2015 International Mechanical Code and the 2015 International Fire Code. No International Energy Conservation Code is on that list. The amendments in Section 500.020 do not delete or amend Chapter 11, Energy Efficiency, of the 2015 IRC, so the residential energy requirements are the ones in that chapter.

That edition sets R-49 for the attic in new work, and R-20, or R-13 plus R-5 continuous for walls. The Department of Energy's recommendation for this climate zone runs higher: R60 for an attic with nothing in it, R49 where a few inches are already down.

Chapter 11 of the 2015 IRC carries the same envelope table as Table R402.1.2 of the 2015 IECC. For climate zone 4 except marine that is ceiling R-49 and wood frame wall R-20 or R-13+5, per the U.S. Department of Energy's 2015 IECC residential provisions summary and the PNNL Building America Solution Center IECC and IRC insulation table.

Do you need a permit to insulate here?

Nothing Ellisville publishes settles this. Its permit lists name the work types it cares about, and insulation is not among them in either direction. It says construction documents are reviewed for renovations, additions and new construction. Insulation, air sealing and weatherization are not mentioned. So we ask the department directly before the first day on site, and whatever comes back, pulling it is our job rather than yours.

The city publishes a plumbing license application and Section 500.030 sets out master plumber, apprentice and master drainlayer licensing. Nothing published requires an insulation contractor to register or be licensed with the city.

Permits and inspections in Ellisville

The published number is 636-227-9660. The department page is here.

Permitting is on us, not on you.

Rebates an Ellisville homeowner can actually use

Most Ellisville addresses are Ameren Missouri electric customers, and Ameren Missouri pays toward insulation through Pay As You Save: $0.20 per square foot on the attic and $0.06 per square foot on air sealing in the 2026 program year, with the rest of the cost recovered through the electric bill. It counts only when the attic is at R-20 or below beforehand and R-38 or more afterward, when air sealing cuts measured leakage by 20 percent, and when the household has lived there for the past year; for income-eligible households, CommunitySavers can include attic insulation at no charge. Income-qualified households can apply to Community Action Agency of St. Louis County (CAASTLC) (314-863-0015) for free weatherization instead. The St. Louis County page and the rebate guide carry the full rules.

Nearby

Ellisville borders Clarkson Valley, Ballwin and Wildwood. These are the ones we also cover, each with its own energy code and permit rule:

Elsewhere in St. Louis County we also cover:

How Ellisville compares with its neighbors

Missouri sets none of this at state level. Across the 7 places in this table there are 4 different adopted editions (2015 IECC, 2015 IRC ch. 11, 2021 IECC and 2024 IECC), and 2 of the 7 publish a permit rule for insulation.

All 21 St. Louis County jurisdictions side by side →

Common questions about insulation in Ellisville

Code and permit facts checked September 10, 2026, rebates October 24, 2026; housing: Census ACS 2020–2024. Sources: ecode360.com (2) · ellisville.mo.us (2, 3) · energycodes.gov · basc.pnnl.gov · data.mo.gov · en.wikipedia.org · censusreporter.org · point2homes.com · ameren.com (2, 3, 4) · energystar.gov · data.census.gov. These change; confirm with the building department at 636-227-9660 or your electric utility first.