Radon Mitigation St Louis: Hire on a Written Bid

You need radon mitigation in St. Louis when a lab result or a buyer’s inspection comes back high. Hire on two things search rank does not prove: a current national certification number, and a written scope for this house. Missouri does not license radon contractors. The first company in results can still do clean work. Treat the ranking page as an ad, then make them put the fan, the pipe, and the post-test on paper before anyone drills.

How to hire radon mitigation in St. Louis

Start with the credential Missouri will not check for you. Missouri law does not require radon contractors to be certified. The same Missouri DHSS radon program still tells residents to hire someone with a current National Radon Proficiency Program (NRPP, a national certification Missouri does not require) or National Radon Safety Board (NRSB, the other national cert) number, and to put that identification on the report. Ask for the number in the first call. If they cannot show a current card, keep calling.

This directory lists 3 radon shops in St. Louis. That is a start list, not a quality ranking. Your check is the number they show you, matched to NRPP or NRSB, plus a scope you can compare. A Missouri house is still a Missouri hire even if a company also works across the river. The state that does not license the trade is also the state whose health department told you which national card to ask for.

DHSS uses 4.0 picocuries per liter (pCi/L, the unit on a radon test) as the action level. If you have confirmed a result at or above that, DHSS says to fix the house. The EPA Consumer’s Guide to Radon Reduction uses the same 4 pCi/L line.

What a St. Louis bid is actually selling

A working system is a fan and pipe that pull soil gas from under the slab and vent it outside. Opening windows or running a bath fan is ventilation. It is not mitigation. If a bid calls the system active, that means the fan is powered.

Name the foundation you actually have. Basement, slab, and crawl space take different pipe layouts. A bid that never mentions your foundation is guessing.

Do not hire from a homepage paragraph about “custom systems.” Hire from a page that maps onto your house. Missouri DHSS mitigation guidance wants a detailed written proposal on how levels will be lowered, and a check after the system is running. Use that as the bar, including for shops that already rank well in St. Louis.

A short bid you can actually use names:

• A current NRPP or NRSB certification number
• Foundation type (basement, slab, or crawl space)
• Suction points (where they pull from)
• Fan location
• Pipe route, including where it exits and how it is supported
• A post-install radon test
• Warranty terms, including whether they transfer if you sell

If a bid skips most of that list, a lower price is not a better price. It is incomplete. For the longer national set of contractor questions, use how to choose a radon mitigation contractor instead of repeating that checklist here.

Quotes, not a handshake

Ask for the written scope before you argue about money. 33% of St. Louis shops in this directory advertise free estimates, and 0% advertise financing, so if you need terms, ask before you sign. A verbal range from a first visit is not a bid. The bid is the document that lists the items above and a total. For national ranges, read how much radon mitigation costs.

You can get that document without agreeing to the install. If they will not write it down, they are not ready to be compared.

If the flag came from a purchase

Buyers in St. Louis see radon on inspection reports all the time. Missouri does not require the seller to test or to mitigate. That is a contract point, not a state mandate. Put mitigation in the negotiation as a written scope with a cert number, not as a vague credit.

If you are still in the test sequence, radon testing when buying or selling covers how buyers and sellers usually handle the flag. For a legal transaction, DHSS wants a professional test, not a kit you ran yourself. Keep the mitigation bid separate from the argument over who pays. The house still needs the same fan and pipe either way.

How long you are waiting on the house

Install is usually a short job. Then you wait on the post-test before you treat the work as done. Crawl spaces, finished basements, and odd pipe routes add time. For the fuller timeline, read how long radon mitigation takes.

Do not delay the hire because you are waiting for a perfect season. The test already told you the air in the lowest lived-in level is the problem. The system runs year round.

Get the bids on paper

Hire in St. Louis on a current NRPP or NRSB number and a written scope. That is the whole method. Rank, a friendly voicemail, and a neighbor’s one-line fan story do not replace those two items.

When you are ready, open radon testing and mitigation cost by city and request written bids from St. Louis shops that advertise free estimates. Compare the scopes side by side. Pick the one that names your foundation, your suction points, and the post-test, then let them install.