Capitol Radon

Service · Des Moines, IA

Crawl Space Radon Mitigation in Des Moines, IA

A vapor barrier and sub-membrane depressurization system designed specifically for homes with a crawl space instead of a full basement.

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Send us your details and we get back to you fast with a written quote.

Quick scheduling

We do not make you wait weeks for a test or an install date.

Locally owned

One shop, one service area, no franchise call center.

A crawl space does not behave like a basement, so it does not get the same radon fix. Exposed dirt or gravel under a home creates a direct, open path for soil gas, which is why crawl space mitigation starts with sealing that surface rather than boring into a slab.

We size and install crawl space systems to match how your particular Des Moines home is built, since crawl space layouts vary a lot more than basement slabs do.

gallery-04.jpg 900 × 900 Radon mitigation project photo

Why crawl spaces need a different approach

Where a basement or slab home gets a suction point drilled into the concrete, a crawl space usually has exposed soil, which means soil gas has a much more open path into the space above it. Sub-membrane depressurization addresses that directly instead of trying to apply a slab technique to dirt.

How sub-membrane depressurization works

A heavy-duty vapor barrier gets sealed across the entire crawl space floor, lapped at the edges and sealed around piers, ductwork and any penetrations. A perforated pipe or a collection point sits beneath the membrane, connected to a fan that draws air from underneath the barrier and vents it outside, the same basic principle as sub-slab depressurization applied to a sealed membrane instead of a drilled slab.

What a good seal actually requires

A membrane that is not fully sealed at the edges and around every pier and post will leak air from the crawl space itself instead of pulling from beneath it, which weakens the whole system. This is the step that separates a system that works from one that looks right but underperforms.

Homes with a mix of basement and crawl space

Plenty of homes across the Des Moines metro have a basement under part of the house and a crawl space under an addition or a different section. In those cases we usually design a combined system, sometimes with more than one suction or collection point, rather than treating each area separately.

Crawl Space Radon Mitigation across Polk County

We run this work throughout Des Moines and the surrounding towns. In places like Des Moines, West Des Moines and Ankeny, no two elevations are exactly the same, so every job gets scoped on site rather than over the phone.

Common questions

Crawl Space Radon Mitigation questions we hear in Des Moines

Yes, clear access to the crawl space floor is what lets us install and seal the membrane properly. We will walk you through what needs to move before the install date.

What neighbors say

Referral work is most of our schedule

PLACEHOLDER review. Two to four sentences in a real customer voice, naming the job and the city.

PLACEHOLDER Name — Des Moines

PLACEHOLDER review. Mention a specific detail — the crack repair matched, the crew cleaned up, the estimate held.

PLACEHOLDER Name — Des Moines

PLACEHOLDER review. Something about responsiveness or the written scope works well here.

PLACEHOLDER Name — Des Moines

Get a straight answer on your wall

Free on-site estimates across Des Moines and Polk County. We look at the actual wall, measure the elevations and send a written scope — no charge and no sales pitch.

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