User:Suiyefrr0y
Radon mitigation for stone foundations can be tricky because the gaps and cracks in old stonework provide many entry points for the gas. A common approach involves sealing visible openings with polyurethane caulk or hydraulic cement, then installing a sub-slab depressurization system if there's a crawlspace or basement. For the best results, it often takes a combination of sealing, ventilation, and active soil suction to reliably lower radon levels beneath the EPA action threshold.