A Checklist for Fixing Foundation Cracks from the Outside

Close up image of cracked foundation on a house

You rely on your foundation to support your entire home, so it's critical to ensure that it remains firm and strong. Not only can foundation cracks cause your home to look rundown and poorly maintained, they can also impact the structural integrity of your property, resulting in long-term damage and costly repairs.

Keep your money in the bank and protect your home by applying a high-quality sealant, like Liquid Rubber Foundation Sealant over the affected areas. It all starts with a thorough inspection of your foundation, looking for any cracks that require maintenance before they become a bigger problem.

With the right tools and products, you can successfully fix foundation cracks on the exterior of your home. In this article, we provide a handy checklist to make sure that your DIY foundation waterproofing goes smoothly and protects your home for years to come.

Inspecting your Foundation

First off, it's important to understand why your foundation is cracking. This knowledge can help you determine the source of the cracks to prevent future occurrences.

Three main causes of exterior foundation cracks are:

  • Settling soil: Settling soil infiltrates your foundation, causing horizontal cracks. These cracks may appear thin or wide, depending on the nature of the damage.
  • Poor foundation waterproofing: In this case, your property may develop vertical or diagonal cracks caused by excessive moisture.
  • Concrete expansion: As the temperature outside changes, concrete naturally expands and contracts. This movement can cause spidery cracks that run vertically or diagonally along your foundation.

While you can fix superficial cracks in your foundation, it's a good idea to call a professional to get an evaluation on cracks that have caused part of your foundation wall to separate. This indicates the possibility of major structural damage you'll have to address immediately.

Liquid Rubber foundation sealant kit

Prepping Cracks

To restore your foundation and get rid of unsightly foundation cracks, start by preparing the area you wish to repair. Gathering together all the tools you will need and reviewing the process ahead of time make the repairs go more smoothly.

For this job, you'll need safety goggles and a dust mask as part of your PPE, plus the following tools:

  • Garden hose
  • Flathead screwdriver
  • Stiff wire brush

As a rule of thumb, you should clear the debris from cracks more than 1 millimeter wide. A flathead screwdriver and stiff wire brush do a great job of clearing out dust, debris and loose material that can compromise the integrity of your seal. For large cracks, consider using an air compressor to thoroughly clean the area.

Pro tip: Prepare all the cracks you want to repair before you begin the foundation waterproofing process. This saves time and allows you to apply the sealant all at once.

Guide to Fixing Foundation Cracks

Here are step-by-step instructions on how to fix foundation cracks, from hairline fissures to larger cracks that threaten the stability of your home:

  1. Choose your preferred method of application for the foundation sealant. Liquid Rubber Foundation Sealant spreads easily with a roller or brush, and you can even use a paint sprayer for even coating.
  2. Apply a generous coating of Liquid Rubber Foundation Sealant to the cracks you have prepared. This product forms a durable seal to start moisture and leaks. It also seals out air, minimizing corrosion, vibrations and noise to improve the function of your foundation.
  3. Apply a layer of Liquid Rubber Geo-Textile over the treated cracks. Geo-Textile is comprised of stitch-bonded polyester, making it one of the strongest materials in the construction industry.
  4. Add a second layer of Liquid Rubber Foundation Sealant over the bonding tape.
  5. Continue adding coats of foundation ceiling as required to reach the desired coverage. Allow each coat to dry until it's tacky to the touch before applying the next layer.

Pro tip: For best results, apply the foundation sealant at temperatures above 10°C/50°F to prevent freezing before the sealant cures.

Benefits of Liquid Rubber Foundation Sealant

Many homeowners choose Liquid Rubber Foundation Sealant for its strength and durability. It's one of the easiest foundation sealants to work with and has a fast drying time — you can apply the next coat as soon as the last one feels tacky to the touch and is uniform in color.

There are few products on the market with greater elasticity than Liquid Rubber Foundation Sealant. It maintains its structure under intense expansion and contraction conditions. In fact, it can elongate up to 900%. That comes in handy during extreme temperatures or sudden changes in temperatures. You can count on Liquid Rubber Foundation Sealant to continue protecting your home.

When you want an eco-friendly, nontoxic foundation sealant, go with the product that protects your foundation as well as your pets, plants and children.

Preventative Measures


Once you have sealed the cracks in your foundation, there are a few other preventive measures that safeguard your foundation. For example, it's important to make sure that your downspouts and gutters are functioning properly. All water flow should be directed away from the foundation.

Move shrubs and small trees located near the foundation. This can prevent root incursion from creating cracks and gaps that threaten the structural integrity of your home. Finally, grade your soil so the land slopes gradually away from your home. These precautions prevent water from collecting near the foundation and ending up in your basement.


When it comes to your home, a strong foundation can protect and safeguard your family and possessions for many years. However, when you notice cracks or gaps, it's important to address them as quickly as possible. Otherwise, you could end up with serious damage that requires a professional to repair.

Turn to Liquid Rubber products to ensure the integrity, quality and longevity of foundation repairs and waterproofing.

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