The Options And Costs to Waterproofing Your Basement Wall

Moisture in basement walls is a relatively common problem. Even if you live in a typically dry city, extra rainfall and snowfall at certain times of the year can cause unwelcome moisture and even floods in basements.

To begin, basements are notoriously gloomy and damp spaces. Even so, too much moisture in basement walls is alarming. And unfortunately for homeowners, a small amount of it may quickly grow into a major issue as it may cause serious problems for your house, ranging from structural damage to deadly mold harmful to you and your family’s health. Needless to say, waterproofing your basement walls is your best move to prevent such headaches. 

Ideally, the best time to waterproof your basement is during its construction, but of course, you might be living in an older building, and maybe you haven't really dealt with this issue until today. Nevertheless, there are a decent number of measures you can take to protect your property from unwanted moisture, ranging from low-cost precautions to high-end professional solutions. Here's everything you need to know about such options and their cost.

Basement Waterproofing Options

The best solution to remedy a moisture problem in your basement walls will depend on how the water gets in, the intended use of the basement area, and of course, the homeowner's budget.

Remember, before taking any action that might affect your basement in a major way, get it inspected by a foundation contractor or a structural engineer.

Interior Waterproofing Options

When leakage is relatively minor or excavation is not an option, interior solutions might be adequate. Your basement may benefit from an internal sealant if it only has small cracks that leak slowly. 

However, it's worth noting that most interior masonry sealants only work on unpainted concrete walls. If your walls are painted, the sealer won't make a solid bond, and the results will, unfortunately, be poor. 

These sealants, which typically come in one and five-gallon buckets, need a heavy-duty brush or roller to apply and can cost you anywhere from $40 to $400 per 100 square feet of wall, depending on the brand and the number of coatings required.

Suppose the walls have numerous large cracks or prior attempts to seal them have ultimately failed. In that case, an interior floor drain system can be a good option. This procedure is identical to installing outside drain tile, except that the excavation is shallow and limited to the basement floor's interior border. 

You can do this task yourself if you know how to use a concrete saw and a jackhammer and have a strong back, though it will be highly time-consuming, and the process won't exactly be a pretty sight. First, you must dig a trench along the basement walls, filling it with pea gravel and perforated drain tile, then construct a sump pit for water collection. Lastly, you'll have to fill the trench with concrete.

Plastic panels are typically put over leaking walls to divert water downhill to the grate. The trench drain, sump pit, and panels might cost thousands of dollars to install, but performing the actual work yourself might save you some money.

Exterior Waterproofing Option

Waterproofing your basement walls from the outside is by far the most effective method. However, doing so necessitates digging dirt away from the foundation's façade on all sides and placing drain tile at the foundation's base.

Before you begin, you'll almost certainly need a permit, and some building regulators will only allow a licensed contractor to work on the project. To be perfectly clear, digging a 7 or 8-foot-deep trench around your foundation is wildly unsafe as it has a significant chance of collapsing. Therefore, it is strongly advised to hire an excavation contractor who uses secure and proven digging techniques and trench bracing. Cheaping out on these service providers might end up costing you more long-term, so make sure only to hire the best.

It's also worth stressing that timing is crucial for this project. Obviously, you want this executed in the dry season as much as possible.

Exterior basement waterproofing using drain tile also requires the construction of a sump pit, which collects water before being drained to the surface by a sump pump. A sump pit can be constructed either inside the home, underneath the basement floor, or outside the house.

As the drain tile is being installed, it will provide ample time to repair, fix, and seal the external foundation walls. Large cracks should be filled with a mortar-based solution, then rolled, brushed, or sprayed with an external masonry sealer once dry. Overall, this is a costly undertaking that might cost upwards of $10,000, but it is the most reliable approach to halt those pesky leaks.

Cost Estimates of Waterproofing Basement Walls

Basement waterproofing is inherently costly, especially when tremendous repair efforts are required. Still, in most cases, this expense may be regarded as an investment in the home's market value. After all, you wouldn't want this problem to cause a major dip in a house's selling price if you wish to sell it in the future.

The cost of this project will vary based on the complexity of the repairs, the property's dimensions, and the current labor rate. Here are some estimates to think about before making a decision:

• If you do it yourself, a simple roll-on interior sealer can cost as low as $40 per 100 square feet.

• Interior waterproofing might cost a homeowner more than $10,000 if it requires the installation of a French interior drain.

• Expect to pay between $70 and $150 per linear foot if the basement needs to be excavated.

• New drain tile may be placed for around $100 per foot once the area has been excavated.

• A sump pump, which collects and pumps water to the surface, can cost anywhere from $1,500 to $3,000.

• In the unfortunate event that structural repairs are required, the cost might rise to tens of thousands of dollars.