The average cost of waterproofing your basement from the outside with a coating or membrane is $3 to $6 per square foot, which typically includes materials and labor costs. The liquid or sheet membrane keeps water from penetrating the basement walls.

The national average cost range to waterproof a basement is $3,000 to $7,000. Most people pay around $5,500 for an interior French drain and a sump pump in a 1,000 sq.ft. basement. This project’s low cost is around $1,000 for applying sealant to the interior walls and fixing one crack with epoxy.

The average cost to waterproof a basement ranges from $500 to $3,500, depending on the extent of the waterproofing and the amount of work involved. Waterproofing is an important precaution for basements that are prone to moisture buildup or leaks, as water damage can cause mold, as well as expensive damage to the home’s foundation.

The interior basement is easier to access, so waterproofing costs slightly less, usually between $500 and $10,000 for a 1,000-square-foot space. However, it’s generally less effective than exterior waterproofing, which typically costs $3,000–$15,000. This is a more involved process that requires excavation and specialized equipment.