A Town Defined by Recent Growth
Much of McCordsville's housing has been built within the last twenty to twenty-five years, as subdivisions expanded outward from the small original town center. These newer homes are predominantly two-story construction with full poured concrete basements, many finished for additional living space, and built to more current construction standards than the area's older farmhouses and small-town homes.
The original McCordsville core, near the historic crossroads and along CR 600 North, retains a smaller number of older homes that predate the subdivision boom, some with basements and others on crawl space or slab foundations more typical of earlier rural construction in Hancock County.
Hancock County's Radon Classification
Hancock County is designated EPA Zone 1, the highest radon potential category, consistent with the rest of Central Indiana. This means McCordsville's newer subdivision homes carry the same baseline classification as older homes near the town's historic core, even though radon potential is driven by geology rather than construction date.
Because so much of McCordsville's basement housing stock is relatively new, radon testing is sometimes overlooked by homeowners who assume newer construction is automatically lower risk. In practice, radon enters through soil gas regardless of a home's age, and newer, more tightly sealed homes can sometimes retain higher indoor concentrations once radon enters.
Mitigation for Newer Subdivision Basements
Most of McCordsville's newer basement homes are well suited to a standard sub-slab depressurization system, since modern poured slabs typically provide a clean, continuous surface for a single suction point. Finished basements require routing the pipe through a closet, mechanical room, or other inconspicuous location to minimize visible impact.
Homes with a sump pit, common in many of these newer subdivisions for foundation drainage, can often use the sealed and capped sump pit as the suction point, which simplifies installation and avoids cutting an additional hole in the slab.
- Sub-slab suction through sealed sump pits in newer subdivision homes
- Pipe routing through closets or mechanical rooms in finished basements
- Sub-membrane or slab-based systems for older crossroads-area homes
- Evaluation of crawl space sections in older rural-era construction
The Older McCordsville Core
Homes near the historic McCordsville crossroads and along the town's original streets are fewer in number but often reflect older rural Hancock County construction, sometimes with crawl spaces or slab foundations distinct from the basement-forward subdivisions surrounding them. These homes are evaluated individually to determine the appropriate mitigation method for their specific foundation.
Installation Timeline
For a typical newer McCordsville basement home, installation can usually be completed in a single day, with the fan and exterior discharge pipe positioned to meet code clearance requirements from windows and property lines. A follow-up test after the system has operated for at least 24 hours confirms the level of reduction achieved.
