Different Kinds of Internal Basement Waterproofing

Basement waterproofing is essential for protecting the structural integrity of your home, keeping your living space dry, and preventing the growth of mold and mildew. While external waterproofing tackles the problem from the outside, internal waterproofing addresses issues from within. It’s often more accessible, less disruptive, and offers solutions even when external remedies are challenging. Let’s dive into the different kinds of internal basement waterproofing methods available.

1. Interior Water Drainage

Interior water drainage is one of the most commonly adopted methods for internal basement waterproofing. The core idea is to channel any water that enters the basement back outside, keeping the area dry.

How it Works: 

A trench is dug along the perimeter of the basement floor. A perforated drain pipe is then laid in this trench. This pipe is directed to either a sump pump or a passive drain, ensuring water is pumped or flows away from the home. The trench is then filled and the flooring restored.


– Effective against water seepage from walls or floors.

– Less invasive than exterior drainage systems.

– Can be combined with other internal waterproofing methods for enhanced protection.

2. Sealants

Sealants, available in both liquid and sheet forms, are applied directly to interior walls and floors. They work by sealing the pores of the concrete or masonry, preventing water from seeping in.

How it Works: 

The basement walls and floor are thoroughly cleaned. The chosen sealant (liquid or sheet) is then applied, effectively sealing off any potential points of water ingress.


– Offers a quick solution for minor seepage issues.

– Can be used as a preventive measure.

– Adds an extra layer of protection when used with other waterproofing methods.

3. Epoxy and Polyurethane Injections

This method is especially effective for basements with cracks in the walls or floors. Epoxy and polyurethane injections seal these cracks, preventing water intrusion.

How it Works: 

After identifying and cleaning the crack, either epoxy or polyurethane is injected. Epoxy binds the crack, essentially welding it together, while polyurethane expands upon contact with water, sealing the crack effectively.


– Provides a strong bond, preventing further expansion of the crack.

– Quick to apply with minimal disruption.

– Effective even for hairline cracks.

4. Vapor Barriers

Vapor barriers, typically made from plastic or foil sheets, are used to prevent moisture from penetrating the basement walls.

How it Works: 

Sheets are applied to the internal side of basement walls. These sheets trap any moisture, channeling it down to an interior drainage system.


– Effective against dampness and humidity.

– Can be combined with other methods for comprehensive waterproofing.

– Reduces the potential for mold and mildew growth.

5. Internal Waterproofing Coatings

These are specialized coatings applied to the interior surfaces of the basement. They are thicker than regular paints and designed to prevent water infiltration.

How it Works: 

The basement surface is prepared by cleaning and fixing any defects. The waterproofing coating is then applied, forming a protective barrier against moisture.


– Offers both aesthetic and functional benefits.

– Can be painted over for decorative purposes.

– Helps in reducing humidity levels in the basement.


Internal basement waterproofing offers a range of solutions to keep your home dry and protect its foundation. Depending on the specific issues faced — be it seepage, cracks, or humidity — homeowners can choose from various methods or combine them for comprehensive protection. Regular inspection and maintenance of your basement will ensure early detection of any water issues, allowing you to address them promptly and keep your home safe and dry.