Exterior Vs Interior Basement Waterproofing: Which One To Choose

Exterior Vs Interior Basement Waterproofing: Which One To Choose

Water from the surrounding soil seeps into your basement through cracks and pores in the walls. Concrete walls, in particular, are porous, allowing water to soak through and cause a wet basement, necessitating basement waterproofing. Furthermore, if you reside in a location prone to high rains, snowstorms, or heavy snow melt, the likelihood of water seepage in your basement rises. When water seeps into your home's internal rooms through the foundation, it can cause substantial damage. Unless you move quickly and begin waterproofing basement walls from the outside or inside, the damage can have a negative impact on the structural integrity and value of your property. To prevent basement water flooding, homeowners can take quick precautionary measures. You should put in enough time and effort to ensure that the house is practically ideal. However, determining the best option for you, such as whether to waterproof the basement wall from the inside or outside, might be difficult. You should also consider hiring a professional business to complete the task. You must consider the facts about basement waterproofing interior versus exterior solutions before deciding which is best for your property.

Interior Basement Waterproofing

Interior basement waterproofing refers to the process of waterproofing basement walls from the inside. Water that seeps into the basement is rerouted this way before it may enter, exit, or leave your property. It is an effective waterproofing solution that is far less obnoxious than outside waterproofing. The inside basement waterproofing system regulates water by quickly draining groundwater before it reaches your floor. It entails the use of interior sealers as well as drainage systems. Interior drainage systems are made up of pipes and drains that are put under the foundation to collect excess groundwater or to capture leaks. Excess water is directed to a big basin known as a sump pit, which gathers water and empties it away from your property through a sump pump. Investing in inner basement wall waterproofing can lessen the chance of water flooding in your basement. These drainage systems are simple to install and often less expensive than outside waterproofing.

Exterior Basement Waterproofing

Exterior basement waterproofing is also a very efficient way to keep water out of your property. Most problems with moist basements are caused by the outside environment. As a result, it is vital to examine the basement's exterior and consider waterproofing basement walls from the outside. Excavation of the soil surrounding your house's foundation is required for an external basement waterproofing system. Because the earth surrounding the home is constantly soaked, it swells and exerts pressure on the foundation, causing it to move and break. The groundwater then seeps into your home through the crevices. However, outdoor basement waterproofing is a time-consuming process that necessitates the use of many tools and machines. To prevent water seepage, a polymer-based waterproof sealant is sprayed to the outer walls of your basement after digging the dirt surrounding the home's foundation.

Differences between the Two Waterproofing

Where it’s installed

The first and most visible distinction is that, as the name implies, external waterproofing is typically performed from outside the basement. This necessitates excavation along the perimeter of the basement. Meanwhile, the majority of the interior waterproofing installation work is done from within the basement.

Sump Pump

Another distinction is that for internal waterproofing, a sump pump system is nearly always required. This is done to prevent water from accumulating inside the weeping tile network. Only if the weeping tile network is linked to a storm sewer would a sump pump be unnecessary. Meanwhile, the demand for a sump pump for outside waterproofing would be determined by the property's specific requirements. Furthermore, if a sump pump is to be utilised for outside waterproofing, it may be installed outside because the exterior waterproofing weeping tile network is also located outside. The sump pump is not required for external waterproofing to keep water out, but it is an excellent technique to keep excess water from collecting around the waterproofed foundation.

Absence of Leakage

Finally, the third major distinction is that external waterproofing is intended to totally keep water out. This implies that once the external waterproofing is installed, water will not be able to reach the basement wall. Meanwhile, inside waterproofing will not totally prevent water from penetrating the wall. However, internal waterproofing will keep the basement dry by strategically using the waterproof membrane and weeping tiles.

Now that the differences between the two waterproofing methods have been, the information below will talk about the factors to consider when deciding between the two.

Factors to Consider

Excavation Area Around Your Basement

This is the most important issue to consider since external waterproofing requires excavation space around your property's base. As a result, inside waterproofing is the obvious best solution for houses that don't have adequate excavation area or none at all.

Moisture Protection

Both waterproofing technologies may be configured to keep the basement dry and free of puddles and leaks. This is accomplished differently for external vs interior waterproofing technologies. The waterproof membrane is installed on the outside of the foundation for exterior waterproofing, which means that water cannot touch the foundation wall. This is used with a matching weeping tile system to regulate soil moisture. A trench and weeping tile network are installed at the foot of the leaking basement walls for internal waterproofing. This network captures leaks that occur through basement walls, and the water is evacuated by a sump pump. Furthermore, a waterproof membrane is laid on the inside surface of the leaking walls to function as a vapour barrier in addition to all of this. We can see from this setting that even with inside waterproofing, water may still infiltrate through the basement walls. However, everything is well-managed and protected by the barrier.

Intended Use

In regard to the preceding point, depending on the function of the basement, some homeowners may prefer outside waterproofing over inside waterproofing. Exterior waterproofing is better for basements that are meant to be long-term living quarters, such as bedrooms, home offices, or rentable spaces. Exterior waterproofing, on the other hand, keeps the area "drier" and does not rely on a running sump pump to accomplish so.


Exterior waterproofing is considered a less intrusive method of waterproofing because of how this type of waterproofing system is constructed, which is primarily from the outside of the basement. In contrast, inside waterproofing necessitates the digging of tiny trenches from within. This implies that inside basement waterproofing may necessitate clearing out the basement prior to installation. If less invasiveness is important to you, outside waterproofing is the preferable alternative.


Exterior waterproofing, on average, lasts longer without maintenance than inside waterproofing. This is mostly due to the fact that interior waterproofing nearly usually relies on a sump pump to keep the area dry. However, in some circumstances, internal waterproofing can be linked to a storm sewer instead, eliminating the need for a sump pump. Furthermore, it is crucial to remember that the quality of the materials and the completeness of the installation both contribute to how long the waterproofing will endure.


Interior waterproofing is generally less expensive than outside waterproofing. However, this just takes into account the initial outlay. Exterior waterproofing may be worth the extra cost, given that it often requires little or no upkeep.

Waterproofing your basement may not be the most popular operation done to homes, but it is one of the most crucial out of the bunch. Waterproofing your basement has many benefits that can save you lots, in terms of time and money. There are two waterproofing methods and they include exterior waterproofing and interior waterproofing. Both are very good investments, there are many factors that could affect which one is best for your home. These factors include the excavation area of your basement, the moisture protection both waterproofing operations provide, the intended use for these waterproofing methods, the invasiveness of the project, the longevity of the waterproofing and your budget. If you are having any troubles with deciding which is best for you, it is best that you contact your local, trusted contractor who specialises in basement waterproofing today.