Waterproofing Basement Walls From Inside Proves Effective

Published On: February 21, 2022

When researching online, Property Managers may inadvertently find that waterproofing basement walls from inside is not enough to keep moisture out of a basement. This is only true if you define waterproofing basement walls as installing a vapor barrier. In all actuality, a vapor barrier is just that – a barrier against moisture, typically installed in a crawlspace – and therefore, an ineffective method of fully waterproofing basement walls from inside. There are in existence, however, very effective alternative solutions to interior waterproofing. In this article, we will discuss effective waterproofing methods for waterproofing basement walls, basement floors, and basements in their entirety.

We will review the connection between damp basements and the air your tenants breathe, how basements get wet, how to properly waterproof a basement, the cost of basement waterproofing, and steps you can take as a Property Manager – in addition to waterproofing – to keep your basements dry.

Damp Basements and Unhealthy Air

Moisture problems are common in basements because they’re below ground. If your tenant doesn’t use or live in the basement, you might not have a problem with this. However, basements are connected to the rest of the home or business, which means bad air created by a damp, moldy basement makes its way up and into the living space, or area where tenants and their customers congregate. That means they are all breathing this in.

Of Course, There Are Other Reasons You Don’t Want a Wet Basement

Today, basements are often used as parking garages, living spaces, or for storing valuable belongings, so a wet, moldy basement can lower property value. Therefore, you’ll want yours to be dry and free from mold and mildew. The only way to achieve this is to thoroughly waterproof the basement. Waterproofing basement walls from inside (which in our area of expertise does not call for the use of a vapor barrier) is a great start to a remedy.

Sources of Moisture in Your Property’s Basement

Wet basements are usually caused by excess water in the soil around and under the foundation, along with poor drainage. The excess water can be caused by various things including, but not limited to:

  • Clogged gutters – If water isn’t flowing freely through the gutters, it can spill over the side of the building and into the soil next to the foundation. From there, it will find a way into the basement.
  • Short downspouts – Short downspouts dump water next to the foundation. Water soaks into the soil and then into the basement.
  • Improper yard grading – The yard, or exterior areas of the property, should slope away from the property’s foundation. If it doesn’t, water will build up in the soil around the foundation and get into the basement.
  • Improperly designed window wells – Water shouldn’t be able to pool inside window wells.
  • Vertical wall cracks caused during the concrete curing process – Vertical wall cracks won’t affect your property’s structural integrity. However, they can allow water to seep into the basement, especially if hydrostatic pressure has been allowed to build up in the soil around the foundation. We’re going to talk about hydrostatic pressure in just a bit.

Sources of moisture in a basement that aren’t related to excess groundwater include:

  • Unvented dryers.
  • Kitchens.
  • Bathrooms with showers.
  • Moisture in newly poured concrete.
  • Open windows that allow humid air to enter.

Why Waterproofing Basement Walls from Inside with Only a Vapor Barrier Is Not Enough

DIY projects that attempt waterproofing basement walls from inside with only a vapor barrier attempt to stop moisture from getting in with this method that is generally reserved for crawl spaces. While it may be less expensive to install only a vapor barrier, and it may work to some extent for a little while, it’s not a long-term solution because it doesn’t eradicate the source of the problem: hydrostatic pressure. Hydrostatic pressure is still there pushing against the wall, and you’re fighting to keep it out. Therefore, the best way to waterproof a basement starts with getting groundwater under control so hydrostatic pressure can’t build up.

So, What Is Hydrostatic Pressure and How Does It Build Up?

Hydrostatic pressure happens when the soil around and under a foundation gets saturated with water that can’t drain off. Eventually, pressure builds up and starts to press against the foundation. Hydrostatic pressure will not only force the water through even the tiniest of cracks and into your property’s basement, but it can also cause cracks in foundation walls.

As long as you have hydrostatic pressure built up in the soil outside the property’s basement walls, you’re going to be fighting a losing battle with moisture. The only way to win the fight is to relieve the pressure via a drainage system.

A Drain Tile System Relieves Hydrostatic Pressure and Is the Best Method of Waterproofing Basement Walls from Inside

A drain tile system is a gold standard when it comes to basement waterproofing. It prevents hydrostatic pressure from building up by channeling excess water in the soil, away from the foundation. Depending on the slope of the yard, or exterior area, the release might be done via gravity drain or a sump pump.

Drain tile can be installed either on the exterior of the structure or inside, under the basement floor.

Exterior drain tile

An exterior drain tile system goes along the outside perimeter of the structure at the footing level. It collects and channels excess moisture in the soil and away from the foundation. Most new homes have at least an exterior drain tile system installed. However, exterior drain tile can also be installed for an existing home. The installation procedure is as follows:

  • The first step is excavation down to the level of the footing.
  • A trench is dug around the foundation’s perimeter.
  • The trench is filled with a few inches of gravel.
  • A perforated, socked drain tile pipe is placed on the gravel.
  • The pipe is covered with a minimum of 2 feet of washed drainage stone, and the remainder is filled with soil.
  • The perforated pipe will now collect excess moisture in the soil and channel it through a gravity drain to daylight.

Interior drain tile

An interior drain tile system goes under the basement floor and prevents hydrostatic pressure from building up under the slab. The excess moisture is channeled into a sump pit and released by a sump pump. The installation is as follows:

  • Everything, including carpeting, is removed from the basement.
  • A jackhammer is used to break up the floor.
  • A trench is dug around the inside perimeter of the basement, along with a sump pit.
  • The trench is filled with gravel, and the perforated pipe is placed in it and covered with more gravel.
  • Concrete is poured over the drain system to provide a sealed system.

The interior drain tile system will now collect excess moisture from water intrusion from under the slab, or through the walls, and channel it into the sump pit, where it will be released away from the foundation by the sump pump.

Other names for drain tile include footing drain, French drain, perimeter drain, and weeping tile.

Other Things You Can Do to Keep Water Out of Your Basement

In addition to a drain tile system, there are other things you as a Property Manager can do to keep water out of your basement including:
Regrade the yard, if necessary – Make sure the yard, or exterior area, slopes away from the building so that water doesn’t collect around the foundation. A landscaper can perform this task, but many Property Managers have their maintenance staff do this as a DIY project.

Clean the gutters regularly – If rainwater cannot flow through the gutters, it will spill over the side of the home and soak into the soil next to the foundation. You don’t want this.
Install downspout extensions, if necessary – Sometimes downspouts are short and dump water too close to the foundation. Extensions are inexpensive and will release the water at some distance from the foundation.
Don’t plant water-hungry shrubs and flowers next to the foundation – You don’t want a reason to pour water into the soil around the foundation.

Cost of Waterproofing a Basement

The cost of waterproofing a basement will depend on where you live, what’s causing the problem, and the chosen solution. The only way to know for sure how much it will cost to waterproof the basement of the property you manage is to contact a foundation repair contractor for an inspection and repair estimate. USS offers free inspections and individualized repair plans to fit the specific needs of each Property Management company.

How To Know When a Basement Needs Waterproofing

A basement might need waterproofing if:

  • There are pools of water on the floor.
  • Water is trickling down the walls.
  • There’s a general feeling of dampness.
  • The base of the wall is saturated.
  • The basement smells of mold and mildew.
  • There’s visible mold and mildew.
  • There’s deterioration in the carpet and/or wood items.
  • The concrete is starting to deteriorate.
  • There’s a white discoloration on the concrete that looks like salt.

If you are looking for the best basement waterproofing company in Nashville, you can count on United Structural Systems. We have the experience, skills, and tools to get the job done right — making us a top-rated waterproofing company in Nashville and beyond. If you have a wet basement (and the property you manage is in our service area in Middle Tennessee, Southern Kentucky, or Northern Alabama), contact us today for a free inspection and repair estimate. We’re happy to help!

Let’s get started!