Types of Waterproofing Membrane

Preventing basement leaks requires attention to detail and an understanding of how water pressure works. With a rainfall that elevates the water table, water will press against the walls of the foundation and floor of the basement with significant pressure.

Taking time to waterproof foundations properly can save tremendously on repair costs later.

Waterproof membranes can prevent water pressure from forcing cracks in a house’s foundation.

Asphalt Membrane

An asphalt membrane comes in a rolled sheet that builders place around the foundation’s walls before they back-fill the area with dirt. The asphalt membrane is an elastic sheet that will cover small cracks if they develop in the foundation’s walls. Asphalt membranes require protection boards to help keep them from slipping.

Polymer-Based Sealant

Polymer-based sealants are chemicals that can be sprayed or painted onto the foundations walls. They are less effective as waterproofing membranes because they cannot cover cracks. They do work for many years, however, to keep the wall of the foundation free from water penetration.

Urethane Sealant

Urethane is a synthetic substance that works well as a prevention and repair tool. Urethane-based sealants are simple to use. The chemical is thick and will help re-seal small cracks in the foundation.

Air Gap Membrane

An air gap membrane requires more labor but works really well on all types of foundations. This sheet is polyethylene, which is a common plastic, and has small dimples throughout it. The dimples allow for air pockets and helps reduce the pressure against the foundation wall. After rolling out this sheet, the builders will attach it to the foundation, making it less likely to move around and become less effective.