When homeowners talk about return on investment, they usually mean kitchens, baths, or curb appeal. Yet water where it doesn’t belong will knock down a sale price faster than dated cabinets. Across the US, buyers and inspectors treat a damp basement as a risk signal and they price that risk into their offers. Industry sources consistently note that remedial waterproofing can recoup a meaningful share of its cost at resale, with survey-style estimates often landing near 30% ROI, especially when work is documented and warranted.