Despite recording some of the driest months in recent years, record rainfalls are still occurring in many parts of the U.S., increasing the importance of a properly operating waterproofing system.

Sometimes, waterproofing systems can prematurely fail in a building or when changes are made to the structure, areas will need to be re-waterproofed. We know that water intrusion has the potential to damage a structure severely, so it’s essential to find the proper repair solutions quickly to avoid costly repairs in the future.

If you are planning a restoration project that involves upgrading or replacing an existing waterproofing system, there are many things to consider to ensure your project is done safely, correctly and on time.

Let’s explore the most important things you need to know about rehabbing the waterproof foundation of your building.

1. Conduct a Comprehensive Assessment of the Building

Gaining a full understanding of existing site conditions will help you determine if you need a repair or replacement for your below-grade waterproofing system. Before beginning any project, it’s always a good idea to speak with an experienced advisor who can help you better understand and evaluate project needs from a building materials perspective.

Getting a licensed professional to inspect the building will help you discover what went wrong with the waterproofing system, where the water intrusion occurred and which repair solution will best solve the problem.

2. Understand the Building’s Construction

A proper building waterproofing system should have the same life as the building itself — but that’s not always the case, which is why you need to always look at the construction of the entire building. The waterproofing system could have deteriorated over time or been compromised by factors unrelated to the waterproofing itself. Regardless of the when, you will need to be aware of the cause in order to fix it properly.

3. Know Your Site Conditions


You also need to evaluate the existing site conditions around your building. Site conditions weigh heavily when choosing the right waterproofing system. There are some important questions you need to ask when determining how to waterproof the foundation.

  • Do you know the water table? Always check to see if a geotechnical report has been conducted before choosing a waterproofing membrane. This will give you insight into why the original product may have been chosen and what you need to consider for a replacement.

  • Is there a history of contaminant soil vapor or gas? Are there ground gases present at the job site? This can include radon, methane and/or carbon dioxide. It’s also important to realize that there may also be contaminant vapor that can permeate your waterproofing membrane.

A Phase 1 or Phase 2 environmental report will identify chemicals present in the soil or groundwater and will help to determine if your waterproofing needs a level of chemical or vapor intrusion protection.

Click here for more in-depth information about what to look for at your building site.

4. Waterproof the Entire Building Envelope

A properly installed below-grade waterproofing system can perform as designed and be free of any leaks, yet water can still be found in the building's basement. Water flows downhill and follows the path of least resistance. If the above-grade areas, like decks, are not properly sealed, water can circumvent the entire below-grade waterproofing system.

Understand the current above- and below-ground waterproofing products in use and what is required from each type to ensure they work properly.

  • Above-grade waterproofing products must be watertight, adaptable to a range of temperatures, resistant to UV light and, in some cases, aesthetically pleasing. Balconies, parking decks, rooftop terraces and plazas need waterproofing to protect the building envelope from moisture ingress.

  • Below-grade waterproofing brings a unique set of challenges. Concrete foundations may be exposed to perched water or nuisance water pressure, even when groundwater table isn’t present. This causes water to collect in the looser soil, keeping it close to the foundation where it can potentially damage the foundation.

5. Do You Need a Repair or Replacement?


Occasionally, waterproofing restoration is not enough, and a complete replacement needs to take place. If you are considering “patching” from inside the structure, know that in most cases, patching will not work. While cementitious coatings and crystalline topical treatments may solve minor issues, it is typically only a temporary cosmetic solution that can redirect or trap moisture and create another problem that could potentially be worse.

Again, this is when consulting a professional becomes an important part of the process. They can determine whether the issue can be quickly resolved, or if the structure will require complete restoration. Here are a few things that need to be considered when determining the severity of water damage:

  • Building’s History: Find out how the building has responded to various weather events and temperature fluctuations over time. These factors can impact a building’s integrity and its ability to prevent leaks.

  • Know the existing waterproofing: Compatibility between the old and new waterproofing systems is imperative. Some legacy systems can present some significant challenges due to their chemical composition. Some products like HydroGel can be applied over the most aggressive systems, like Coal Tar Pitch.

Contact an EPRO Representative Today

Thanks to our 25-year track record with project success, we’re proud to be the company of choice for building envelope consultants and building owners.

Our experts are ready to help with answers about choosing the best waterproofing and contaminant systems for restoration and rehab projects and can help ensure their integrity through proper testing.

Have questions or want to learn more? Reach out to us about collaborating on a project.