Window replacement and siding replacement across greater St. Louis, both sides of the river — with the permit rule and the window energy code looked up for every city we work in.
Window replacement and siding replacement across greater St. Louis, on both sides of the river: full-frame and insert windows in wood, vinyl, fiberglass and clad, and siding in vinyl, insulated vinyl, fiber cement, engineered wood and steel.
Full-frame and insert windows in wood, vinyl, fiberglass and clad, built to the U-factor and SHGC your city actually requires.
Vinyl, insulated vinyl, fiber cement, engineered wood and steel, over a new water-resistive barrier lapped in the right order.
Cheapest to buy and to install, never needs painting, and one of the better claddings for keeping a wall dry. Insulated vinyl is flatter, quieter and more dent-resistant.
Fiber cement is dimensionally stable, does not feed insects and is non-combustible. Engineered wood is lighter and easier to cut, with a warmer look.
There is no hail rating for siding, and on a St. Louis claim the argument is usually about matching. We will tell you what we see, including when we do not think you have a claim.
On a house built before 1978 the federal lead rule is on the job, and in a local historic district the ordinance can decide what a window is made of. We check what both require before anything is ordered.
Water gets into a wall at the openings. The flashing that stops it sits behind the cladding, which means the only time anyone can inspect it, correct it or replace it is while the siding is off. That is why we do both, and why we will tell you when doing both at once is cheaper than doing either one twice.
Full-frame and insert, wood, vinyl, fiberglass and clad
Vinyl, insulated vinyl, fiber cement, engineered wood and steel
Siding is the visible decision. The barrier and the flashing behind it decide whether the wall is still sound in twenty years — and once the siding is back on, nobody can check them.
Rot behind siding and a failed egress measurement are not unlucky. They are the two things that turn up on these jobs, so we look for both before you sign anything.
Net clear opening on every bedroom and basement window against the egress rule. Safety glazing at every location the code names. The roof-to-wall intersections, for a kickout that is missing. The build year, which decides whether the lead rule is on the job.
Permit or no permit, which energy code edition applies, what U-factor that puts on the window, whether the city wants the contractor registered, and whether you are in a historic district that regulates what the window can be made of.
Including what happens if we open the wall and find soft sheathing — priced per square foot against the area actually found, agreed before we start, rather than discovered as a number on the final invoice.
New barrier, correct lap order, flashing at every opening and every transition, kickouts installed. Photographed as we go, because once the siding is on you have no way to check and neither does the next owner.
Every window operated. Every opening checked. On a pre-1978 house, the lead-safe compliance summary you are owed within thirty days.
Contractors quote resale return and energy payback selectively. Here is the whole table for the census division Missouri sits in, from the industry's own annual report, including the rows that do not flatter us.
Fiber cement siding is the only one of these that returns more than it costs. Windows are the worst performer on the list, and that lines up exactly with the energy arithmetic: windows are a maintenance and comfort purchase, not an investment.
Sources: jlconline.com · jlconline.com
| Project | Job cost | Resale value | Recouped |
|---|---|---|---|
| Siding replacement, fiber cement | $23,470 | $24,236 | 103.3% |
| Siding replacement, vinyl | $18,907 | $15,365 | 81.3% |
| Window replacement, vinyl | $22,781 | $15,932 | 69.9% |
| Window replacement, wood | $26,149 | $17,897 | 68.4% |
Replacing single-pane glass with ENERGY STAR windows saves about $493 a year in this climate zone on EPA's modeling. Replacing older double-pane saves about $253. Do that arithmetic against a real quote before anyone tells you windows pay for themselves.
The full calculation, and the cheaper alternative most companies will not mention →
In Missouri, every municipality adopts its own building and energy code, or does not. Across this one metro that produces at least 6 different legal requirements for the same replacement window, and several places where there is no requirement at all. Cross the river and Illinois fixes one standard for the whole state and forbids any city from making it weaker or stronger.
| One example of each | Adopted energy code | Window has to meet |
|---|---|---|
| Brentwood | 2024 IECC | U-0.28 |
| Kirkwood | 2021 Energy Conservation Code | U-0.30 |
| St. Louis City | 2018 IECC | U-0.32 |
| Unincorporated St. Louis County | 2015 IRC energy provisions (no separate IECC adopted) | U-0.34 |
| Webster Groves | 2015 IECC | U-0.35 |
| Wentzville | 2021 IRC energy provisions, locally amended | U-0.40 |
Every jurisdiction we work in is listed, with its own page and its own sources. See the whole table →
It depends entirely on which side of a city limit the house sits on, and the range in this metro is wide. St. Louis County lists re-siding among the ordinary repairs that need no permit at all. Edwardsville deleted its entire residential exemption list, so everything needs one. Granite City uses a money threshold. We looked up all 45 jurisdictions we work in — the answers are here, city by city, with the published wording.
Missouri has no statewide energy code, so the number changes at every city limit — we found 6 different U-factor requirements across this one metro, plus places with none at all. Illinois is the opposite: one statewide code, and municipalities are forbidden from making it either weaker or stronger. The full breakdown is here.
Almost certainly not, and anyone telling you otherwise is selling. EPA's own modeling puts the saving at about $493 a year replacing single-pane glass in this climate zone and about $253 replacing older double-pane. Against a real St. Louis job that is a payback measured in decades. Replacement windows are worth it when the windows are failing, when the house is uncomfortable, or when you want the house to look different. As a pure energy investment against a window that still works, the arithmetic does not close. Here is the whole calculation, with sources.
Yes, and it is the single biggest thing people are not told before work starts. 58.3% of homes in this metro were built before 1980, and on anything pre-1978 the federal lead rule applies to both trades. Window replacement is never exempt from it, at any size. A whole-house re-side blows past the exterior threshold immediately. The firm has to be EPA-certified, a certified renovator has to be on site, and you have to be given the EPA pamphlet before work starts. What that actually looks like on a job.
Both, and often together, because the two jobs share the part in the middle. The flashing at the head and jambs of every window opening lives behind the siding. Re-siding is the only moment in a house's life when you can get at it. Doing windows first and siding two years later means opening the same wall twice and paying for it twice.
Each one has its own page, because each one has its own answer on permits, on which energy code applies, and on what that puts on the window.
See every city we cover →Tell us the address and roughly what you are looking at. We will tell you what your city requires before we tell you what it costs.
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