What is the difference between exterior and interior foundation waterproofing?

Exterior foundation waterproofing preserves the structural integrity of your foundation, and does not allow any water or moisture to seep through the block, brick or concrete. Moisture presence in your foundation can lead to deterioration over time, and result in costly foundation repairs or complete foundation rebuilds. Waterproofing internally can be a lot less expensive, and works more as a diversion process for water. Water is still able to enter through the foundation, but is diverted underneath the floor area into an internal weeping tile system.