Why Vapor Barriers Alone Aren’t Enough to Keep Your Crawl Space Dry

A lot of homeowners believe that laying down a plastic liner — also known as a vapor barrier — is all it takes to dry out a wet crawl space.

But here’s the truth: a vapor barrier is only one piece of the puzzle.

Without proper drainage and moisture control, even the best liner will fail to stop the real problem: groundwater, humidity, and pressure pushing into the space beneath your home.

At PierPoint Foundation Solutions, we specialize in creating full-service crawl space moisture systems — not quick covers that hide the issue.

💡 What Is a Vapor Barrier?

A vapor barrier is a heavy-duty plastic sheet laid across the ground inside your crawl space. Its job is to:

• Slow down moisture evaporation from the soil

• Help create a cleaner, drier under-home environment

• Reduce the risk of mold, mildew, and pests

While it’s an important component, it doesn’t block water from entering — it just reduces surface-level moisture.

🚫 Why Vapor Barriers Can Fail on Their Own

When installed without a drainage plan, a vapor barrier can become:

• A trap for water pooling underneath

• Wrinkled or shifted by rising hydrostatic pressure

• Moldy or damaged due to ongoing seepage

• Disconnected from walls, piers, or seams — letting moisture sneak in

Without managing the water around and under your crawl space, the barrier becomes a band-aid, not a fix.

💧 What You Actually Need to Keep It Dry

Here’s what separates a real moisture solution from a plastic cover:

✅

EZ-Flow or French Drain System

Channels groundwater away from your crawl before it reaches the liner.

✅

Sump Pump Installation

Collects and removes water actively — not passively — especially during storms or high water table events.

✅

Sealed Vapor Barrier with Mechanical Fastening

Liner should be bonded to the walls and piers — not just laid loosely — to fully isolate moisture.

✅

Wall Insulation and Air Sealing

Helps prevent humid outside air from entering and condensing inside the crawl.

✅

Crawl Space Dehumidifier

Controls ambient moisture that seeps in from the soil or outside vents, especially in warmer months.

🧱 The PierPoint System

When we encapsulate a crawl space, we don’t just roll out plastic.

We assess the slope, measure water levels, check humidity, and build a system based on:

• Your soil saturation

• Local flood risk

• Air movement

• Under-structure design

• And long-term protection goals

And everything we install comes with a lifetime transferable warranty.

🛠️ Your Crawl Space Deserves More Than a Liner

If you’ve got standing water under the plastic… or if the barrier was installed years ago and you’re seeing musty smells or warped flooring again — let’s take a look.

📞 Get a Full Moisture Evaluation from PierPoint

We offer free inspections to determine why your crawl space still feels damp — and what to do about it.

📍 Serving all of Arkansas

📅 To schedule an inspection, contact Dakota Treece:

📞 (501) 284-9330

📘 Message us on Facebook @PierPointFoundationSolutions

🔗 Book Your Free Moisture Check

Plastic doesn’t fix water. Systems do. Let’s build one that lasts.