Waterproofing that Works

Water penetrating foundation walls is a leading cause of property damage. The foundation itself can weaken and crack if continuously exposed to water. And once the water penetrates your foundation, mold and mildew can ruin a basement and whatever is inside.

To keep your home dry and mold-free, you need to have your foundation properly waterproofed, ideally before damage happens.

My home is new. Do I still need waterproofing?

Unless you specifically requested full waterproofing on a new-construction home, its unlikely that your foundation is waterproof.

If you are lucky, there might be tar dampproofing, but exterior foundation waterproofing is not standard, even in areas with soggy clay soils and high water tables.

Black Tar Won’t Cut It

Waterproofing tar is the old-school way to keep a basement dry. Years ago most builders didn’t even think about “waterproofing” a foundation. In the last few decades, many builders in wet areas started slapping foundation tar onto poured concrete walls and calling it waterproofing. It’s better than nothing–but not by much.  

Foundation tar is only good as dampproofing. It’s a tough barrier that makes it harder for moisture in damp soil to seep through your foundation.

Once water has pooled up around your foundation, the asphalt is useless against water pressure. It also won’t stop damage from expansive soils, like the clay commonly found across New Jersey and Southeast Pennsylvania.

Get Technical

Construction technology has come a long way in the past thirty years. Technologies like carbon fiber and breathable polymer coatings were once limited to research labs and operating rooms. Now, they can be found at the local hardware store.

While there are a variety of products that can do the job, it is important that a waterproof foundation uses a membrane which actually forms a seal against water. Slapping black goo on your walls won’t do much more than bare concrete or a coat of housepaint to prevent long-term water damage.

Triple Protection

Best practices for waterproofing a foundation draw on three types of protection to keep your foundation as dry and mold-free as possible.

• An exterior foundation sealer is applied to block moisture and standing water.
• A french drain is installed to carry excess moisture away from the home.
• The trench for the french drain and vapor barrier is filled with gravel to promote drainage and keep expansive soil away from your home.

Moisture Barriers

Whether you live in an expensive city like Chicago, or in a suburban home in New Jersey, the most important part of a foundation waterproofing project is a barrier that surrounds a basement and prevents groundwater from reaching the porous concrete or cinderblock walls.

Contractors have quite a few options to create this barrier.

Spreadable Coatings

There are several brands of spreadable asphalt coatings which can be used as waterproofing membranes. Unlike older tar coatings, these newer coatings are flexible and won’t crack under water pressure. As rubber-based products they are also self-healing, so minor tears or damage from freezing and thawing soils will not compromise the protection of your waterproofing.

Sprayable Coatings

Several companies offer polymer-based coatings that can be sprayed on with a paint gun. Very similar to the undercoating on a 4×4 truck, these barriers form a gapless seal around your foundation walls. 

Contractors have to pay special attention to places where pipes penetrate the foundation and any joints or cracks in the poured foundation walls.  

These spots are the most likely place for water to penetrate, and the easiest to overlook

A contractor will need to totally seal around any pipes or outlets. After spraying the first layer, the contractor should stop and spot-fill any gaps or spots where the coating measures too thin. The gap where a basement floor slab meets the foundation wall should also be filled with a compatible sealant.

Plastic Sheeting

A cheaper alternative to a spray coating is the application of thick vapor barrier sheets against the foundation walls. These self-adhesive sheets require the foundation to be primed and any large cracks to be filled before they can go up.

Once in place, they provide a strong, waterproof barrier between the ground and your wall.

Drainage Mat and Gravel Fill

After the waterproof coating has been applied, waterproofing best practice is to apply a drainage board in front of it. This board will keep fill soil from resting against your walls, channel moisture to the french drain, and protect the vapor barrier from abrasion and burrowing animals. Some installation will mount this mat to foam insulation sheets before attaching it to the foundation walls.

A layer of gravel will be filled in around your drainage mat to protect it from clay soils.

French Drain

A french drain is a sloped trench with a pipe that carries water away from your foundation. Farmers have been using the technique for centuries with clay pipes, but modern french drains use PVC pipes and mesh debris guards to stay clear and effective for years. 

The french drain will work with a drainage mat to keep water from building up agianst your house. By backfilling the trench with rocks, the waterproofing company creates a sort of natural aquifer that will keep the space around your foundation relatively dry under normal conditions.

This is the best way to prevent mold and a cracked foundation because even a perfect waterproof membrane is not meant to act like the hull of a ship all the time. Water might not get through the barrier, but it can still put pressure on the poured concrete and eventually crack the foundation.

Picking the Right Contractor

A full waterproofing project is far beyond the scope of DIY. You need to excavate large sections of earth, precisely apply specialty coatings, and fill the whole project with tons of gravel.

It’s important to work with someone you can trust. It’s also important to make sure the contractor is providing quality work.

Ask what materials the contractor is using. Think twice about inferior foundation tar coatings–saving a few hundred dollars won’t mean much if your foundation springs a leak six months later.

Dry Basement Solutions is a family run company with over 20 years in the industry. To schedule a consultation call  201-258-4540 or visit their website.

Why You Need a Crawlspace Vapor Barrier

• Save Money on Heating and Cooling

Moisture finding its way in from a crawl space can make your home feel hot and humid. With a vapor barrier in place, you can run the A/C less and save on cooling costs.

• Protect Your Home From Water Damage

Most people think about flooded basements and burst pipes when they think of water damage, but consistent high humidity can be just as bad for the wood and masonry beneath your house.

• Prevent Mold and Mildew

Mold spores are dangerous to human health. Inhaling them can cause everything from allergic reactions to long-term disease, and the worst of the worst carry deadly toxins. Mold loves dark and damp places, so the best way to prevent mold from growing in your crawlspace and spreading to the living areas is to keep it dry with a vapor barrier.

Is your vapor barrier installed properly?

Vapor barriers are more than just a sheet of plastic tucked somewhere under the floorboards. To actually keep a home dry and insulated, vapor barriers need to be properly installed. A poorly installed vapor barrier can do more damage to your home than none at all!

This guide will show you what to look for to see if your current vapor barrier can pass muster.

Three Ways NOT to Install a Vapor Barrier

With Gravel On Top

A lot of contractors have been putting down a layer of thick plastic vapor barrier, then layering gravel on top, This isn’t a vapor barrier–it’s a swimming pool!

It seems like these contractors are thinking that they will stop groundwater from rising up into a basement. They’re wrong. All this kind of “vapor barrier” can do is trap rainwater. It won’t be able to absorb into the ground because there is a thick plastic sheet in the way, and the gravel will act like a perfect aquifer. Water will have one place to go: up into your foundation.

While often well-intentioned, installing a vapor barrier incorrectly like this is worse than not having a vapor barrier at all.

Stapled to a Ceiling

When homeowners try to install a vapor barrier in a crawlspace, it is quite common for them to staple sheets of thick plastic to the ceiling of their crawlspace as a “vapor barrier”.

This kind of vapor barrier doesn’t do a thing to stop moisture from getting into your home. It does guarantee wood rot beneath the plastic sheet. Just like with the gravel-over-plastic installation, a vapor barrier plastic stapled to the ceiling will actually trap moisture, not block it.

This will be even worse if the barrier covers any pipes or ducts. Cool metal surfaces like air ducts collect condensation during the summer.

Normally this evaporates without anyone noticing, and no harm was done. But with a plastic sheet covering the duct, the condensation will end up soaking into your floor joists. It’s a recipe for mold.

Wrapped Around the Walls

Many contractors will try to sell homeowners something that looks like a full encapsulation system by wrapping vapor barrier sheets around the walls of a crawl space and stapling them to the wood sill plate.

There are a couple of huge problems with this kind of system.

Staples punched through the plastic act like little steel wicks. Any moisture that gets between the foundation walls and the plastic will wick right into the wood house frame. This not only defeats the purpose of a vapor barrier but introduces serious risks of wood rot, mold, and structural damage.

When contractors do these kinds of simple wraps, they almost never take the time to tape the seams where sheets overlap. Moisture can easily wick through these gaps.

At the end of the day, this kind of installation only looks like a vapor barrier. In practice, it won’t come close to giving your home the protection of a crawlspace vapor barrier.

The Right Way to Install a Crawlspace Vapor Barrier

The correct way to install a vapor barrier in a crawlspace is surprisingly simple. Sheets of 6 mil vapor barrier should be used to cover the floor area, overlapped by 12 inches.  No gravel coatings, no stapling things to the ceiling, and no gaps–just a clean, professional installation.

Dry Basement Solutions: Contractors You Can Trust

If your crawlspace or basement has problems with dampness or mold, call the experts at Dry Basement Solutions for a consultation. With over 25 years of experience in the remediation industry, the family owned and operated team is ready to tackle mold and basement water damage needs.

Visit their website or call 201-258-4540 for a consultation.