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  • Writer's pictureNusite Group

How to Waterproof a Basement from the Outside.

Updated: Sep 9, 2020

This blog will explain the basics of exterior waterproofing (outside the home). All products discussed can be found at the Waterproofing Warehouse.

Before you start waterproofing your basement, I recommend calling a professional. Nusite Contractors Ltd. is a great waterproofing company, that offers free, no-obligation quotes. They do great work, and use great products.

If hiring a professional waterproofing company is out of the picture, or you are a contractor looking to get in the industry, read this blog to learn the basics of Exterior Waterproofing. Please remember this is a recommendation and only one of the few ways to waterproof a home.

If you find any foundation issues while waterproofing PLEASE contact a foundation or concrete expert.

Exterior Waterproofing Side View

What supplies are needed for external waterproofing?

Step 1: Excavation

The first step of the exterior waterproofing process is the removal of the dirt and clay surrounding the compromised foundation walls.​​ Dig until you reach the homes footings.

Supplies Needed:

Step 2: Foundation Check and Repair (Apply Protective Layer One)

Once the compromised wall is fully exposed you should complete a thorough check of the foundation. At this point, all cracks and damaged areas are strengthened with hydraulic cement (Protective Layer One).

Supplies Needed:

Step 3: Apply Protective Layer Two (Aqua-Bloc 720-38)

Apply the elastomeric membrane (aqua-bloc 720-38) to the foundation wall. This membrane is a pliable polymer-modified asphalt, which heals itself if new cracks develop. This process should be used because it prevents water from penetrating the high-pressure areas of your foundation. Unlike tar, the elastomeric membrane is designed to keep all water out, instead of just slowing the water down.

The Process:

  1. Put on your disposable gloves.

  2. Scoop the Aqua-Bloc out of its tub and spread it throughout the entire foundation wall. You can spread the Aqua-bloc with disposable application gloves.

  3. Cut your yellow Jacket to the same size as the foundation wall. Press the Yellow jacket onto the wet Aqua-Bloc and press it until the Aqua-Bloc seeps all the way through.

Supplies needed:

Step 4: Apply Protective Layer Three (Planton Membrane)

This layer is made of a polyethylene-dimpled drainage mat, which is a heavy gauge mat that is ideal for protecting the elastomeric membrane (Protective layer 2). The mat uses dimples to create an air gap so all moisture can be channelled to the drain.

The Process:

  1. Cut Your Membrane to fit the foundation wall.

  2. Once you have the correct size, hold your membrane against the wall and use your shots and/or pins to stabilize it.

  3. Place and secure moulding at the top of your membrane. This stops water from sneaking behind your drainage mat.

Supplies Needed:

Step 5: Install the New Footing Tile

The new footing tile is designed to keep the level of water below the floor of the basement. Its purpose is to keep the basement both pressure-free and leak-free.

The process:

  1. Remove the old weeping tile.

  2. Connect and place your new weeping tile at the bottom of your membrane. Use fittings if needed.

  3. Cover your weeping tile with 3/4 clear gravel.

Supplies Needed:

Step 6: Backfill and Clean Up

Backfill with 3/4 clear gravel and then you can restore your homes' landscaping.

Supplies Needed:

About The Waterproofing Warehouse

The Waterproofing Warehouse sells all your waterproofing supply needs! Our goal is to provide you with quality products at great prices. As individuals who have worked in the waterproofing industry for over 30 years, we know how frustrating buying products can be. Let us become your one-stop-shop to make your job a little easier.

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