Sealed Crawl Space

In Cary, foundation cracks, air intrusion, and unsealed crawl spaces cause a predictable set of problems for homeowners. A fully sealed and encapsulated crawl space is a definitive solution — it addresses existing moisture and mold concerns while preventing the next round of problems before they start.

How We Seal a Crawl Space

We apply advanced vapor barriers across every square inch of ground-exposed surface, forming a complete moisture blockade rather than a partial fix. All joints, seams, and potential entry points are sealed to prevent future water intrusion. It's designed to integrate with your home for the long term, not act as a quick patch.

What "Sealed" Actually Means: The Vents

The part people ask about is the foundation vents, because closing them sounds like exactly the wrong thing to do. Those vents were built on the assumption that outside air dries a crawl space out. In a Carolina summer it does the opposite: warm, humid outside air enters a cool crawl space, hits framing and ductwork that are below its dew point, and condenses there. The vent is not ventilating — it is delivering moisture, every humid day, all summer.

Sealing them closes that path. The vents are permanently sealed and insulated rather than fitted with covers that get opened again, and the space is then dried and conditioned from the inside instead of being left to the weather.

"Won't That Cause Problems?" — The Two Common Worries

Pipes freezing. Sealing helps rather than hurts. An open-vented crawl space tracks the outside temperature, which is why pipes down there freeze in the first place; a sealed, insulated space stays much closer to the temperature of the house above it.

The space getting musty because it can't breathe. This is the right instinct applied to the wrong mechanism. Musty crawl spaces are humid ones, and the vents were a major source of that humidity. A sealed space is kept dry actively — with a dehumidifier sized for it — rather than passively, which is what makes it drier than a vented one rather than stuffier.

Sealed vs. Fully Encapsulated

These overlap and the words get used interchangeably, so it is worth being precise. Sealing is closing the space off — vents, seams, and every path from outside air and ground moisture into the crawl space. Full encapsulation is that plus the rest of the system: liner up the walls, wall and rim joist insulation, and conditioned air.

In practice most jobs here end up as the full system, because sealing without conditioning leaves humidity already inside the space with nowhere to go. Which you need depends on what the inspection finds, and a vapor barrier alone is a legitimate answer for some homes.

Benefits of a Sealed Crawl Space

• Energy Star rated system for improved efficiency
• Better heating and cooling efficiency by reducing the load on your HVAC system
• Reflective insulation with a 97% reflectivity value to cut radiant heat loss
• Class A / Class 1 fire rating for safety
• Reduced conditions for mold and fungus growth
• Improved indoor air quality throughout the home, not just in the crawl space

Insulation Completes the System

Sealing keeps moisture out; insulating the walls and rim joist keeps temperatures consistent and adds another layer of defense against moisture that can foster mold growth. Together, sealing and insulation form a system that keeps your home warmer in winter, cooler in summer, and drier year-round.

If Mold Is Already Present

Mold under your house is a health hazard, not just a nuisance — it's linked to sinus infections, allergies, and respiratory problems. Our remediation process contains the affected area, removes water- and mold-damaged materials, dehumidifies to prevent regrowth, cleans structural surfaces, and uses HEPA filtration to clear the air before we seal the space.