Vapor Barriers and Crawl Space Encapsulation in Dover, NH

At NH Dry Basement, we are more than familiar with the need homeowners have for crawl space dehumidification, encapsulation, and vapor barrier installation in Dover, NH. Crawl spaces often accumulate moisture from groundwater vapor, which leads to various issues. Our solution: installing vapor barriers in your Dover crawl space, along with encapsulation and dehumidifiers to effectively mitigate crawl space water problems all year long.

What Is a Vapor Barrier?

A vapor barrier acts as a shield against ground moisture impacting your home. It consists of rolls of standard sheet plastic placed on the ground within a crawl space. This barrier keeps the water in the ground from turning into vapor or condensing. The U.S. Department of Energy refers to a vapor barrier as a vapor diffusion retarder, highlighting that, while plastic sheeting with sealed seams offers significant protection, it doesn't completely block all moisture.

This sheeting is crafted from reinforced polyethylene (poly) in varying thicknesses and strengths, typically ranging from 6mm to 23mm. The thickness of a millimeter is 0.001 inches, making a 6mm sheet 0.006-inch thick. NH Dry Basements goes above and beyond to protect your home by installing 20mm to 120mm thick barriers in crawl spaces, depending on your specific needs, for a reinforced poly vapor barrier installation you can trust.

encapsulated crawl space
encapsulated crawl space

Benefits of Installing a Vapor Barrier

Installing a vapor barrier is an affordable solution to a potentially severe issue. Its advantages include:

  • Blocking moisture from rising through your flooring
  • Preventing mold and mildew growth
  • Protecting against structural wood rot
  • Deterring pests that thrive in damp conditions
  • Avoiding moisture-related wiring problems and rust
  • Enhancing your home's energy efficiency with additional insulation
  • Making your crawl space cleaner and more accessible
  • Other problems caused by moisture

Moisture poses a significant risk to the structural integrity of your home. It can lead to mold growth and decay on wood framing and joists, especially in crawl spaces where it's dark and susceptible to water accumulation. Addressing moisture is crucial, especially for new room additions or below-grade flooring in your Dover Home. Crawl space vapor barriers play a vital role in mitigating water damage to walls, ceilings, and floors. Dehumidifiers help to reduce excessive moisture in the air during particularly wet months.

Mold and Mildew

Moisture can lead to the proliferation of mold, mildew, and fungi, which are challenging and costly to eradicate. These issues can damage floor cavity insulation and structural components. Preventative measures or remediation are necessary, particularly in crawl spaces with limited light and ventilation.


Wooden structural elements like joists, sills, posts, and beams are susceptible to rot when exposed to water over the course of time.

Rodents and Other Vermin

Moisture attracts various pests, such as carpenter ants, termites, rodents, and even larger animals like skunks and armadillos.

Vapor Barriers vs. Crawl Space Encapsulation

While a vapor barrier is designed to slow down moisture damage by sealing the ground, our experts in Dover also offer crawl space encapsulation which provides additional, comprehensive protection. It involves sealing the entire crawl space—including the walls—with thicker sheeting, often 10mm or more.

Partner With Us for Crawl Space and Basement Waterproofing

NH Dry Basement is dedicated to providing exceptional service to homeowners in Dover, NH, with crawl space repair, vapor barriers, encapsulation, and dehumidifier installation. Our certified experts bring meticulous attention to detail, outstanding craftsmanship, and a commitment to customer satisfaction. Trust us to protect your home from moisture-related problems. Contact NH Dry Basement today to request a free inspection and estimate!