Insulating a house in Edwardsville runs on one state energy code, not a local one — here is the R-value it sets, what the city does and does not ask a permit for, the Ameren Illinois discount your address qualifies for, and how old the housing here really is.
Edwardsville runs to about 20 square miles and roughly 26,474 people. It sits about 18 miles northeast of downtown St. Louis. That is roughly 10,609 housing units, and the attic above almost all of them is the cheapest thing in the house left to fix. The community dates back to 1818. We cover ZIP codes 62025 and 62026.
Our job history shows nothing in Edwardsville so far. Plenty of sites will show you a number here anyway.
The typical home in Edwardsville dates to around the mid-1980s. Houses of this vintage usually got batts or blown fibre 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.
Built out steadily through the 1970s-80s, with only modest growth (about 3%) since 2020.
That includes Leclaire. Housing age and construction shift across Edwardsville, sometimes by decades within a few streets, which is why we look in the attic before quoting rather than after.
Incorporated in 1818, Edwardsville's Leclaire Historic District was a planned 19th-century industrial cooperative village later annexed into the city (1934), and Historic Saint Louis Street carries more than 50 homes dating from the mid-19th to early-20th century.
Housing from this stretch in Edwardsville generally got a real attempt at insulation — a real layer in the attic, batts in the walls — so the argument here is rarely about starting from nothing. It is about the gap between what was standard then and what is recommended now, and about the parts nobody insulated at all. Recurring finds: batts stuffed into the rim joist rather than sealed, insulation missing entirely above a cathedral or tray ceiling, soffit vents blocked solid by insulation blown over them with no baffles, and can lights punched straight through the ceiling plane. A house from this era is usually a top-up plus a day of sealing, not a rebuild.
Edwardsville enforces the 2018 IECC named locally; Illinois Energy Conservation Code (2024 IECC with Illinois amendments) governs by state law. The city's remodel permit requirements handout lists the codes it enforces: 2020 National Electrical Code, 2021 International Residential Code, 2021 International Building Code, 2018 International Energy Conservation Code and the Illinois State Plumbing Code. The city adopted its updated International Codes on July 7, 2022, effective January 1, 2023. The locally named 2018 IECC is an older edition than the Illinois Energy Conservation Code now in force, and 20 ILCS 3125 does not let a municipality set residential energy standards less or more stringent than the state code.
Under that edition the required attic value for new work here is R-49, and walls R-20 + R-5 continuous, or R-13 + R-10 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.
Table R402.1.3 of the 2024 IECC as amended for Illinois, climate zone 4. Madison County is in climate zone 4 per the NAIMA IECC compliance guide for Illinois homes.
There is no published answer for Edwardsville. Neither the permit-required list nor the exemption list mentions insulation or air sealing at all. 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. The remodel permit requirements handout states minimum insulation levels that remodel work must meet, but the city does not publish insulation on its own as a listed permit type. The permit page describes permits as required for remodeling existing buildings and for additions, wall relocation, plumbing fixtures, electrical upgrades and lighting changes; insulation alone is not named. That silence is not permission and it is not a prohibition. We settle it with a phone call before the crew is scheduled.
The city publishes no contractor registration or licensing requirement for insulation work. The remodel handout requires an Illinois-licensed plumber for plumbing work if the applicant is not the owner-occupant.
The published number is 618-692-7535. The department page is here.
Permitting is on us, not on you.
Edwardsville is on the Illinois side, and the Illinois programme is the more generous of the two by a wide margin. Ameren Illinois publishes flat per-unit discounts applied by the contractor rather than mailed to you as a cheque. On Ameren Illinois' 2026 discount table: $1.10 per square foot for attic insulation and the same for wall insulation, $2.00 per linear foot for rim joist, $3.00 per linear foot for crawl space wall, and $0.70 per cubic foot per minute (CFM) of air leakage reduced for air sealing.
Two conditions decide whether any of that reaches you. Air sealing has to be pre-approved before the work starts — do it first and ask afterwards and the money is gone. And only a registered Ameren Illinois Program Ally can apply the discount at all: a contractor who is not on that list cannot get it for you, whatever they say on the doorstep. Ask which they are before you sign.
Compare that with the Missouri side of the metro, where the same attic gets an on-bill programme paying $0.20 per square foot instead, and only if the attic started at R-20 or below. Same weather, same houses, different utility regulator.
If the household income qualifies, the work can be free rather than discounted. Madison County is served by Madison County Community Development under the Illinois low-income weatherization program — 618-692-8940, 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.
Edwardsville sits in all eight counties are iecc 2021 climate zone 4 on the same map the Department of Energy uses to write its recommendations, which is why the figure it recommends for an attic here is R60 rather than something borrowed from a national advert. Heating and cooling both matter at this latitude. The energy code and rebate guide sets out the numbers behind it.
Elsewhere in Madison County we also cover:
Illinois sets the residential energy code from Springfield, so these figures agree across the county — what changes here is the permit desk, not the R-value.
| City | Energy code | Attic R required | Permit to insulate | Building dept. |
|---|---|---|---|---|
| Alton | Illinois state code | R-49 | Not published | 618-463-3500 |
| Collinsville | Illinois state code | R-49 | Not published | 618-346-5200 |
| Glen Carbon | Illinois state code | R-49 | Not published | 618-288-2615 |
| Granite City | Illinois state code | R-49 | Not published | 618-452-6218 |
Free assessment, a measured R-value, and photos you keep either way.
The code edition Edwardsville 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.
Edwardsville has not published a rule for it. In practice that means one call to the building department before the job starts, which is on us rather than on you.
Ameren Illinois publishes $1.10 per square foot for attic insulation and $0.70 per cubic foot per minute (CFM) of air leakage reduced for air sealing on its 2026 discount table, applied by the contractor rather than paid to you directly. Two conditions decide whether it reaches you: air sealing has to be pre-approved before the work starts, and only a registered Ameren Illinois Program Ally can apply the discount at all. The federal 25C credit ended for work placed in service after 31 December 2025.
The typical home in Edwardsville dates to around the mid-1980s. Houses of this vintage usually got batts or blown fibre 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. 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 Edwardsville, and we would rather say so than put a number on this page that is not real.
Illinois does not license insulation contractors as a trade, though it does run the residential energy code from Springfield rather than leaving it to each city. Municipal registration varies — some Metro East cities require a business licence, others require none at all. What matters more in practice is whether the contractor is a registered Ameren Illinois Program Ally, because only an Ally can apply the rebate.
Energy code, permit and department details for Edwardsville 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: cityofedwardsville.com · cityofedwardsville.com · cityofedwardsville.com · library.municode.com · en.wikipedia.org · censusreporter.org · point2homes.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.