Radon Levels in Katy TX — What the EPA Data Shows

Texas Radon Zones

The EPA divides the US into three radon risk zones. Texas is mostly Zone 2 (moderate, 2–4 pCi/L predicted average) and Zone 3 (low, <2 pCi/L). The Gulf Coast including Fort Bend and Harris Counties is predominantly Zone 3 — lower risk than the midwest and mountain west. However, EPA recommends testing all homes regardless of zone, because soil composition varies significantly within zones and individual homes can exceed 4 pCi/L even in low-risk zones.

Why Zone Doesn't Tell the Whole Story

Radon levels depend on the specific soil beneath a home, not just the general area. Homes on soil with higher uranium content, homes with more cracks and openings in the foundation, and homes with basements (rare in Katy) can have elevated radon regardless of county averages. The only way to know your home's level is to test — charcoal canister tests are available for $15–$30 and can be sent to a lab.

Entry Points in Katy TX Construction

Houston-area homes are predominantly slab-on-grade construction — no basement, concrete slab directly on soil. Radon entry points: construction joints at the slab perimeter, cracks in the slab, pipe penetrations, and the micropores of unsealed concrete. Sealing these entry points with epoxy meaningfully reduces radon entry even if it doesn't meet the EPA's definition of a radon mitigation system.

Epoxy as Part of a Radon Reduction Strategy

For homes testing between 2–8 pCi/L (moderate elevation), epoxy floor sealing is a reasonable first-step mitigation measure. For homes above 8 pCi/L, a sub-slab depressurization system (installed by a certified mitigator) is recommended — epoxy alone is insufficient. We recommend testing before and 90 days after epoxy installation to document the effect on radon levels.