Foundation layout, the number of pressure zones, and pipe-routing difficulty usually have the largest effect on a residential proposal. Home size matters when it creates more slab area or separated zones, but square footage alone does not determine the design.
The six factors to check in every quote
Illustrative cost ranges from our calculator
The examples below use a 1,800-square-foot, two-story home with a standard pipe route. They are calculator outputs, not market averages or contractor bids. The point is to show how one input changes the same model.
| Foundation | Planning range | Model midpoint |
|---|---|---|
| Slab-on-grade | $1,450–$2,500 | $1,850 |
| Basement | $1,550–$2,650 | $2,000 |
| Crawl space | $1,750–$3,000 | $2,250 |
| Mixed foundation | $1,950–$3,350 | $2,500 |
Model date: September 3, 2026. Review the complete allowances in our calculator methodology.
Why a higher radon result does not automatically mean a higher price
The radon result tells you the urgency and the reduction needed. It does not reveal how air moves beneath the home. A relatively compact home with good sub-slab communication may need a straightforward system even when its test result is high. A home with a lower result can still be more involved when it has additions, multiple foundations, or a difficult vent route.
The EPA says costs vary with the size and design of the home and the reduction method needed. It recommends estimates from qualified mitigation contractors rather than relying on one national price.
How to compare contractor proposals
- Ask each contractor to describe the intended suction point, fan location, and vent termination.
- Confirm whether diagnostic testing, electrical work, permits, labels, and a system pressure indicator are included.
- Request the fan and workmanship warranty terms in writing.
- Confirm who provides the post-installation radon test and what happens if the first design does not reduce the level enough.
- Compare scope before comparing totals. A lower quote may simply exclude work shown in another proposal.
Sources and limits
The system descriptions and cost guidance on this page follow the EPA’s radon mitigation cost guidance and Consumer’s Guide to Radon Reduction. Our optional ZIP lookup applies a state-level BEA price factor. It still does not know city-specific contractor rates, travel charges, permit fees, soil conditions, or concealed construction problems.