Close this search box.

Defending Your Home from Basement Moisture with Exterior Waterproofing

exterior basement waterproofing
exterior basement waterproofing

The basement is an often overlooked area of the home. Most people don’t go into the basement unless they need something or if they are doing laundry, so it tends to be out of sight or mind.

That is why most homeowners consider the basement a wasted space, feeling that it will never offer anything beneficial to the home. They may even have standing water in the basement so often that they consider it normal.

Although standing water and high moisture levels may be regular occurrences in the basement, they should not be considered normal parts of having a basement. High moisture levels can do more than make the basement damp and uncomfortable; it can threaten your home’s foundation.

That is why many homeowners have decided to take control of the situation and have their basement waterproofed. One option is exterior waterproofing. What is it, and is it worth doing?

Exterior vs. Interior Basement Waterproofing

There may be many different options used in a basement waterproofing job. Still, one of the first choices is if you will be doing interior basement waterproofing or exterior basement waterproofing.

Although both accomplish something similar, limiting moisture in the basement, the approach is very different. The following are brief descriptions of exterior and interior basement waterproofing, along with some pros and cons of each.

Exterior Basement Waterproofing: If you are considering exterior waterproofing, you are doing something that will be proactive. Unlike interior waterproofing, which essentially cares for any moisture already in the basement, exterior waterproofing is designed to keep moisture from entering the basement in the first place.

The largest task in exterior basement waterproofing involves digging a trench around the foundation. The depth of the trench depends on the circumstances, but 8-10 feet is not out of the question.

After the walls are cleaned, a waterproof sealant or membrane is put on the wall, and a French drain is installed. Any excess water will be drained away from the home to a lower area.

In most cases, exterior basement waterproofing is done during the construction process. It can also be accomplished after the fact, but due to the excavation, it can be more expensive.

The primary advantage of exterior basement waterproofing is the proactive nature of the job. You stop water from entering the basement, and since you are draining the soil, you reduce hydrostatic pressure and the possibility of foundation damage.

On the other hand, the cost is extensive if you are doing exterior basement waterproofing after the home is built. It can be time-consuming and can damage surrounding landscaping. Everything around the home must be considered, including HVAC, sidewalks, driveways, and decks or patios. These will be disturbed during the process if they are close to the foundation walls.

Interior Basement Waterproofing: If you already have a problem with high moisture levels in the basement, interior basement waterproofing is one option to consider. For the most part, interior waterproofing involves sealing the inside of the basement walls and draining any water that may enter the basement from the inside.

Most interior basement waterproofing jobs involve installing a drain tile system to drain any water into a sump pit. The water can then be pumped to the outside using a sump pump.

Repairs may also be necessary for any existing damage, such as cracks in the wall or slab due to hydrostatic pressure. In many cases, a dehumidifier is also installed to control humidity in the basement as well.

Most people consider interior basement waterproofing because it is less expensive and does not involve quite so much disruptive construction.

It is an excellent way to waterproof the basement, and many people have enjoyed using the basement for storage or even additional living space after having an interior waterproofing job done.

The bottom line is that either can get the job done, but exterior basement waterproofing is more proactive, while interior basement waterproofing tends to be more reactive.

Symptoms that a Waterproofing Solution Is Needed

In most cases, problems will not occur in the basement without them showing in other areas of the home. This is especially true of moisture issues.

Be aware of the following symptoms that will typically show when a waterproofing solution is needed. These symptoms may occur gradually or could happen all at once when the issue is advanced.

Be aware of the following symptoms that will typically show when a waterproofing solution is needed.

Foundation Cracks: Cracks in the foundation are common problems associated with moisture. These occur due to excess moisture in the soil surrounding the foundation, which puts hydrostatic pressure on the foundation walls.

Evidence of Moisture: Obviously, any standing water or high humidity levels clearly indicate a moisture problem in your basement. There may also be other possible symptoms, including efflorescence.

Efflorescence is typically white and forms on the surface where water exists and evaporates. As the moisture evaporates, it leaves behind a salt deposit that is still visible.

Infestations: A damp, dark basement is also ideal for pests to move in. You may notice problems with bugs or even rodents. This type of infestation does not often stay limited to the basement.

Mold: This issue could also be attributed to high moisture levels, but mold also needs a food source and the right temperature to survive. Most basements provide all three of those necessary features for mold to thrive.

If you notice any mold growth in the basement or if you have a mildew smell, then you have a mold problem. Some basements may also have what they call an ‘old house smell,’ which is Volatile Organic Compounds (VOCs) left over from decayed mold and bacteria.

High Energy Bills: Many people complain about high energy bills, but it is not always the fault of the energy company. Moist air does not stay in the basement. It enters the home through the stack effect.

As warm air exits through the attic and roof, new air enters the home from the basement. It has been estimated that approximately 50% of the air you breathe in your home originated in the lower level.

Since the moisture level is higher in the basement, it will also be higher in the rest of the home. Moist air is harder to heat or cool, making energy bills more costly.

Water Drainage: An Important Part of Waterproofing

Although several tasks may be necessary for exterior waterproofing, one task always considered is a water drainage solution. Something similar is also considered for interior waterproofing.

A few primary types of drains are used in such a drainage system. These drains keep moisture away from the basement, clear moisture from the basement, and keep additional pressure off the foundation walls.

How A Sump Pump Works

Drain Tile: A perforated pipe may be buried below the surface outside the foundation wall to catch any additional water and drain it away from the foundation walls. French drains are installed in gravel, allowing the water to filter into the perforated pipe without silt clogging it.

French drains collect the water and redirect it away from the foundation. Depending upon the lay of the land and property lines, the water can be drained to a lower area of the property, the street, or other suitable location.

Sump Pit/Pump: A sump pit is an important part of many basements. Water is channeled into the pit using a drain tile system where it is held until it reaches a certain level.

Once the water reaches the predetermined level, it triggers the sump pump to turn on and pump water out of the sump pit. It drains to a suitable location outside the home and foundation, where it can naturally flow away.

Basically, sump pumps come in two different varieties: pedestal and submersible. Each of them has its own advantages or disadvantages, and they both have the task of draining the sump pit to a more suitable location. Battery backup systems are also beneficial, just in case the power goes out.

It’s Time to Enjoy Your Dry Basement

Exterior basement waterproofing is your first step toward having a clean, dry, and comfortable basement. Due to the aforementioned stack effect, the air you breathe in your home will also be drier, healthier, and cleaner.

There are many benefits to having a dry basement, but most people tend to use them for extra storage.

In addition, a basement can be used for extra living space after waterproofing. With the installation of a dehumidifier, living in the basement or keeping it as a separate room for one of the children or even a spare room for guests can be very comfortable.

The bottom line is that once you have a dry basement, you can use it. Most people consider the basement a lost cause, but you will realize it is one of the most valuable parts of the home.

If you are ready to have your basement waterproofed, it’s time to contact the professionals. Call us today or fill out the convenient form on our website to get the process started.


Dave Epp

Dave is the President at Epp Foundation Repair with over 27 years of experience in the industry. Dave has worked on thousands of foundation, basement, concrete, and crawl space repair projects since 1993. Dave is involved in several civic and church organizations and enjoys coaching youth sports, mainly football, golfing, and elk hunting.



Foundation Leak

Signs You Have A Foundation Leak

Under house insulation

Is it worth insulating under the house?

Sump pump cover

Are you supposed to cover a sump pump?

The Complete Basement Waterproofing Guide For Midwest Homeowners

Discover the most common ways water gets into your basement and what you can do to keep it dry.

Epp Basement Waterproofing Guide