Interior vs Exterior Basement Waterproofing

The last thing you want to worry about is seeing water dripping from your basement ceiling or pooling on the ground. If that’s the case, how do you know if you need to waterproof basement from inside or outside? In this blog, we dive into the differences between interior vs exterior waterproofing, what the pros and cons are, and how to determine which method would be best for you.

What is Interior Basement Waterproofing?

Interior basement waterproofing is when contractors tackle the moisture issue from inside your home. It can also be referred to as internal waterproofing. Any leaks that need to be remedied will be done so inside of your house, and this is the optimal solution if your basement already has a moisture issue.

Oftentimes, accumulated water is pumped out of the space. It’s good to know that this option also deters the water source from getting back into your house, as contractors can fix or install better drainage systems.

When to Waterproof Basement from Inside 

Interior waterproofing is used to address moisture issues in your basement, help prevent mould growth and protect interiors. This treatment is best suited in situations where exterior access for existing buildings is limited, or when excavation is not possible. Waterproofing the basement from the inside is ideal for urban homes or properties with established landscaping.

Benefits of Interior Basement Waterproofing

There are several benefits to internally waterproofing your basement:

  • It’s more affordable. 
  • It can prevent toxic and damp air, further protecting you from dangerous health conditions.
  • It will make the space easier to clean. 
  • It will provide your home with a stronger foundation.
  • There is barely any disruption in the installation process. 
  • This option usually has a backup system.

Drawbacks of Waterproofing Basement from Inside

How To Waterproof Basement From Inside

There are several systems involved when interior basement waterproofing.

Common systems include crack repair, sump pumps, and French drains, applied waterproofing (either drylock paints or crystalline solutions), dehumidifiers, and vapour barriers.

What is Exterior Basement Waterproofing?

While interior basement waterproofing can rectify the issue from the inside, the exterior alternative prevents the water from getting into the foundation in the first place.

Contractors will expose the base of your home and apply exterior waterproofing membrane. This will help keep moisture away from the foundation’s walls.

When Is Waterproofing Basement Walls From Outside Necessary?

Waterproofing basement walls from outside, also referred to as exterior waterproofing, is used for new constructions, historic buildings, high water table areas, and locations prone to heavy rainfall. This method offers long-term protection against water intrusion.

Benefits of Exterior Basement Waterproofing 

Let’s explore the pros of exterior basement waterproofing: 

  • It’s a better option if you use your basement for storage purposes. 
  • There’s no need to move furniture or appliances, as everything is done outside. 
  • The drains will be placed outside.
  • It’s a more complete way to prevent flooding. 
  • This option prevents deeper damage.

Drawbacks of Waterproofing Basement from Outside

How To Waterproof Basement From Outside

Any system applied on the outside of your home, or the exterior of your basement walls is involved when exterior waterproofing.

Some common examples of how to waterproof basement from outside include wrapping, drains, guttering, and grading.

How To Decide Between Interior Vs Exterior Waterproofing?

There are many factors that influence whether interior waterproofing or exterior waterproofing is right for you. Since every home is unique, your decision to opt for an interior solution over exterior work may differ from another home that requires the opposite.

With that said, consider the following:

  • Existing water issues in your basement: Depending on whether you are trying to resolve a minor issue before it worsens, or you are dealing with a specific on-going problem, this can impact which of the two waterproofing methods you choose. 
  • Your budget: Interior waterproofing is typically more affordable than exterior methods so it’s important to determine if your budget can account for the expenses involved in each method. Think about the cost of waterproofing basement from the outside versus from the inside. 
  • The age of your home: Extensive repair work may be necessary to waterproof a basement in an older home. 
  • How your home was constructed: A home with a poured concrete basement may not be able to be waterproofed with one method, as opposed to a home with a blockwork wall that can.

Consulting with a basement waterproofing expert of ours will help you to make an informed decision between exterior and interior waterproofing.

For more information on basement waterproofing in Ottawa and knowing which option is best for you, call Summit Drain and Plumbing at 613-355-7566 or contact us via our website. Our services are professional and reliable, ones that you can trust!

FAQ

A main sewer line blockage can cause water to backup in random places. For instance, you run your washing machine and notice your sink overflowing – this can be a clear sign that you have a clogged drain line.

If you have ruled out a potential sewer drain clog, you can rinse your sewer drain by flushing it with water. When you flush your lines, try adding a bit of drain cleaner to the water. A great place to flush your sewer line is the toilet – a larger amount of water and drain cleaner can enter your system quickly and easily. Unfortunately, if you do this when you have a clog, it can cause backup and potential flooding – if this is the case, clear the clog first.

You should generally know if your sewer line is blocked with slow drainage. The purpose of the sewer line is to take all the water drainage away from your house via sinks, bathtubs or toilets – if you find that there is slower drainage in one drain then you can essentially clear that yourself using a drain snake or a plunger.

There is confusion regarding when you are responsible for sewer line repair. While some may believe that the homeowner is only responsible for repairing the part of the line that’s on their property, this is not the case. Sewer lines consist of multiple sections, the upper lateral, lower lateral and the main line. The city is only responsible for repairing the main sewer line.

If issues with the main sewer line cause damage to your lower lateral, which is most likely where the damage would generally first start – the city would repair this damage when they work on the main sewer line. Unfortunately, if there is backup and flooding on your property from the main sewer line, then the city would not be responsible. It is best to follow up with the city to see if they will repair any damage in these cases.

Unpleasant smells coming from your drains is indicative of sewer line issues and damage. You should always take these types of smells seriously as it could be toxic fumes slowly releasing from the sewer below into your home.

There are a number of ways to clear a slow drain using products found around the home:

Bent Wire – If you do not have a drain snake, you can try using a stiff wire – like one from a clothes hanger, leaving the hook to enter pipes and pull out any clogs. Try to make sure you don’t push debris further into the pipe.

Homemade Flush – Mixing baking soda and vinegar can dissolve any materials that are potentially clogging your drain pipes. This is a good and much safer alternative to store-bought chemical cleaners.

Toilet Plunger – Like plunging a toilet, you can try using this on your drains. Using a plunger on your drains can help get things moving by using suction. This should be enough to fix any mild blockages.

Aged drain pipes are at risk for corrosion which can lead to breaks. Summit Drain has both the technology and expertise to fix this if necessary.

Yes. Drain pipes are durable, but not meant to last forever. If you live in an older home in Ottawa, most likely the pipes are made from copper and can collapse in this day and age.

When it comes to a collapsed drain, call Summit Drain. We use trenchless technology to replace sewer pipes made from original materials without ruining your property.

Rock salt
Rock salt helps by removing moisture from the roots, which in turn kills them. Two lbs should do the trick, pour 1 down the toilet. Flush until gone. And repeat with the next. Then leave for 12 hours and don’t run any water.


Foaming root killers
Another effective way to treat roots in pipes is with foaming root killers. Pour powder into toilet and flush. It will foam upon contact with water. Not only does it help dissolve current roots, but also helps to protect against future ones.


Copper sulfate
Copper sulfate is another good option. Available at most hardware stores, pour roughly half a cup into toilet and flush until gone. Leave the home and take all pets and family members along. This is a toxic substance and banned in some places.


Should I replace old pipes?
There does come a time where it makes sense to replace your pipes. Over time they crack and corrode. It is recommended to begin routine inspections once your home reaches 50 years in age. For plumbing Services in and around the Ottawa area, nobody does it like Summit Drain.

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