There is often confusion about the differences between dampproofing and waterproofing and when one product should be applied instead of the other. While both products are used below-grade (meaning below ground level), the difference is simply that unlike dampproofing, waterproofing can withstand hydrostatic pressure, the force exerted due to the presence of liquid water. Waterproofing is also typically more expensive because of its properties.

In practice, this means a building with a below-grade occupied space needs to have waterproofing applied to the exterior because we know the exterior soil will hold moisture, especially during a rain event. This moisture then attempts to enter the building through the foundation wall.

In a single-story above-grade structure, the transition from the slab edge to the footing could be treated with waterproofing or dampproofing. However, because we do not have a finished, occupied space below-grade, we can instead use dampproofing, saving the client in costs. See the details below for an illustration of each.