Adding square footage permanently changes your home's value. A properly permitted, engineer-stamped addition built by screened general contractors passes every inspection and holds its value through every market cycle.
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Most contractor problems are preventable. These checks take under an hour and catch the most common hiring mistakes.
Ask for their MO contractor license number, then verify it yourself at the state licensing website before signing anything.
Request a certificate of insurance. Call the carrier directly to confirm general liability and workers' comp are active.
Get at least three written bids. Any quote more than 30% below average is a red flag, not a deal.
Ask specifically about permit requirements for home addition. A contractor who says "no permit needed" for structural work is a liability.
Read recent Google and BBB reviews for complaint patterns, not just star averages. One-star reviews reveal how disputes get resolved.
AboveBoardPros gives you a head start on checks 1 and 2.
In the states our automated check reaches, we cross-check the business against the state registry, and we read the certificate of insurance where a contractor provides one. You still confirm the trade license with your state and ask for a current certificate before you sign.
$40,000 to $150,000
Typical Home Addition projects in St. Louis run $40,000 to $150,000.
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This is what we have checked in St. Louis so far. Every contractor we found is shown here, not ranked.
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Here’s what we’ve checked on Midtown Home Improvements so far.
Multiple quotes to compare, with our checks shown on every listing. Decide with confidence.
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AboveBoardPros is a matching service. These checks apply to the pros we list. We connect you with independent contractors and do not perform the work ourselves.
Typical Cost Range
$40,000 to $150,000
St. Louis market estimate
In St. Louis, home addition typically ranges from $40,000 to $150,000. Getting three written bids from licensed contractors is the most reliable way to calibrate your specific project.
Timeline depends on project scope. Ask for a written schedule before work begins, and specifically ask about material lead times and permit inspection windows: these cause most delays.
Home additions always require a building permit. The permit process covers structural plans, foundation, framing, electrical, and final inspections at multiple stages. No licensed contractor will begin an addition without pulling permits, and unpermitted additions must be disclosed in any home sale.
Yes. St. Louis enforces active licensure and insurance. Ask any contractor for their license number and verify it at the MO state licensing website before signing a contract.
In Missouri, contractor licensing is tracked by the Missouri Division of Professional Registration. You can look up any contractor's license status directly at https://pr.mo.gov/licensee-search.asp. To file a complaint or check for consumer alerts, use the Missouri Attorney General's consumer complaint page at https://app.ago.mo.gov/app/consumercomplaint. Where our automated check reaches a state, we cross-check the business registry for the pros we list, and every listing shows what that check found.
For the pros we list, we cross-check the official state business registry where our automated check reaches, scan the contractor's own website for credential claims, and pull public business signals. Partners get a further step: a person reads the state record and the insurance certificate before the account opens. The How We Screen key on this page explains each step.
Pros checked against state business registries where our automated check reaches. Free, no commitment.
Nearby areas: St. Louis
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