Foundation Waterproofing: Protecting Your Home from Moisture

A strong foundation is essential, not just in life but also for your home. One of the most important aspects of a solid foundation is ensuring it is properly waterproofed. Without effective waterproofing, your basement could turn into a damp, dark space—far from the bright, functional area it could be.

Why is Foundation Waterproofing Important?

Concrete is not waterproof; it’s a porous material that allows water to pass through over time, especially when cracks form or when under hydrostatic pressure. Even a flawlessly poured foundation can still allow moisture to seep in. This is where exterior foundation waterproofing becomes critical—it serves as the first line of defense to keep your basement dry and comfortable.

Types of Foundation Waterproofing

Several waterproofing methods can be used, and the choice depends on the soil, drainage, and foundation type. The most common methods in Renfrew County include:

Liquid-Applied Waterproofing

The traditional choice for foundation waterproofing is a tar-based liquid applied to the foundation. This method involves:

• Stripping the foundation wall of forms.
• Cleaning it of dust and debris.
• Applying the tar-based liquid with a sprayer or paint roller.

Once dried, the liquid creates a barrier against groundwater and dampness. This method is suitable for both concrete block and poured concrete foundations. For concrete blocks, a rough coat of parging is applied before the liquid, while poured concrete foundations require an additional tar coating over the form tie holes.

Peel-and-Stick Membranes

Peel-and-stick membranes are a modern and effective solution. They consist of:

• A rubberized asphalt waterproofing layer.
• A protective top layer.
• A backing sheet that is removed just before application.

Typically, these membranes come in 36-inch wide rolls, applied vertically along the foundation wall, from grade level down to the bottom of the footing. Each layer overlaps the previous one to ensure a continuous barrier. A primer is used to enhance adhesion.

Benefits include:

• Consistent thickness of the waterproofing material.
• Ease of installation with just a utility knife.
• Immediate visibility of any damage, allowing for quick repairs.

Peel-and-stick membranes are versatile and can be used on concrete block, poured concrete, and ICF (Insulated Concrete Forms) foundations.

Dimpled Membranes

Dimpled membranes, resembling egg cartons, are another effective waterproofing option. These are plastic rolls that:

• Cover the entire height of the foundation with a single length.

• Are mechanically fastened to the top of the foundation and sealed with caulk.

This method excels in retrofit situations where existing foundations are being upgraded. Unlike liquid and peel-and-stick membranes, dimpled membranes can be installed on damp, soil-covered foundations without the need for cleaning.

What About Under the Basement Slab?

Water can seep through concrete slabs as well, so it's crucial to protect the basement floor from moisture. There are two main methods:

Poly Vapor Barrier: A cost-effective solution, using a poly vapor barrier beneath the slab, with seams overlapped and taped with construction sheathing tape.

Rigid Insulation: For a more energy-efficient option, use 2-inch rigid insulation beneath the slab, offering both a vapor barrier and an R-10 insulation value.

At Quality Homes & Renovations, we assess your foundation’s unique needs and choose the waterproofing solution that best fits your site conditions. Whether you're building a new home or retrofitting an older one, our team ensures your foundation is properly protected from moisture using the most effective products on the market.