The proper thickness of plastic to use in a moisture barrier for your crawlspace depends on various factors, including the climate in your area, the level of moisture in your crawlspace, and the intended purpose of the barrier. The most common thicknesses for crawlspace moisture barriers are 6 mil and 10 mil. Here’s a breakdown of these two options:

6 Mil Plastic:

    • 6 mil plastic is the more economical choice and is commonly used for crawlspace moisture barriers.
    • It is 0.006 inches (0.15 mm) thick and provides a basic level of protection against moisture.
    • This thickness is suitable for areas with moderate humidity levels and limited moisture intrusion.
    • Durability: 6 mil plastic is considered less durable compared to thicker options.
    • Strength: While it provides a basic level of protection against moisture, it may be more susceptible to tearing or punctures, especially during installation or maintenance activities.
    • Longevity: 6 mil plastic can last for several years if installed and maintained properly. However, its lifespan may be shorter compared to thicker options in areas with high moisture levels or significant wear and tear.
    • Ideal Conditions: 6 mil plastic is suitable for crawlspace environments with relatively moderate humidity levels and minimal moisture intrusion. It can effectively prevent moisture seepage and reduce the risk of mold growth in less challenging conditions.

10 Mil Plastic:

    • 10 mil plastic is thicker and more robust compared to 6 mil plastic.
    • It is 0.01 inches (0.25 mm) thick and offers greater strength and durability.
    • This thickness is recommended for areas with high humidity levels, heavy moisture intrusion, or homeowners seeking additional protection against potential punctures or tears.
    • Durability: 10 mil plastic is more durable and robust than 6 mil plastic.
    • Strength: The thicker material offers increased puncture resistance and tear strength, making it more resilient against potential damages during installation and maintenance.
    • Longevity: 10 mil plastic typically has a longer lifespan compared to 6 mil plastic, especially in areas with high humidity levels and more demanding moisture conditions. It can withstand wear and tear more effectively over time.
    • Ideal Conditions: 10 mil plastic is recommended for crawlspace environments with high humidity levels, significant moisture intrusion, or areas prone to potential damages, such as sharp objects or debris in the crawlspace.

Other Considerations:

  • Reinforced Plastic: If durability is a top priority, consider reinforced plastic with multiple layers and a reinforcing grid in between. Reinforced plastic offers the highest level of strength and puncture resistance, providing superior durability in challenging crawlspace conditions.
  • Installation and Maintenance: Regardless of the thickness, proper installation, and regular maintenance are essential to ensure the longevity and effectiveness of the moisture barrier. Avoid dragging heavy objects over the plastic, and be cautious during any crawlspace activities to prevent accidental damage.
  • Professional Guidance: It is crucial to seek professional guidance to assess your crawlspace’s specific needs and recommend the appropriate thickness and type of plastic for your moisture barrier. A qualified contractor or crawlspace encapsulation expert can help you make an informed decision based on your crawlspace’s unique characteristics.

Choosing the right thickness depends on your specific crawlspace conditions and moisture concerns. If your area experiences significant moisture issues or you want a more robust moisture barrier, 10 mil plastic is preferable. It increases durability and may be more damage-resistant during installation and maintenance activities.

However, if your crawlspace generally remains dry with minimal moisture concerns, the 6 mil plastic can be sufficient to create an effective crawlspace moisture barrier at a more budget-friendly cost. Ultimately, the right thickness of plastic for your crawlspace moisture barrier will depend on the specific conditions of your crawlspace and your budget. Choosing a high-quality, appropriately thick plastic can significantly contribute to the success of your crawlspace encapsulation in preventing moisture-related issues and improving indoor air quality.