Insulating Crawlspace Bottom of Floor Joist

Crawlspace Insulation - Bottom of Floor Joist

Installation Instructions

  • Inspect the crawl space and make any needed repairs before installing InfraStop® double bubble insulation.

  • Check the crawl space to determine whether the floor joists are 16” or 24” on-center.

  • Determine if there are water pipes and heating ducts which hang below the floor joists. They will need to be insulated. InfraStop® Pipe Wrap and Duct Insulations are designed specifically for this use. There is no need to wrap water pipes or duct work that fall between floor joists. InfraStop® will provide adequate insulating without extra wrapping.

  • Start at the end of the house and face staple to the bottom of the floor joists. Seal seams with InfraStop® Foil Tape to create a vapor barrier. At the end, staple up to the sub-floor or band board.

  • Note: Existing mass insulation in the joist cavities must be dry prior to installing the InfraStop® product.

Crawlspace Insulaton - Staple Tab Roll Sizes

Crawlspce Insulation - Square Edge Roll Sizes

Thermal Insulation

R-17 Crawlspace Insulation - Bottom of Floor Joist

Product Information

InfraStop® Insulation products are a group of technologically advanced materials. They are ideal for new construction or retrofit applications in commercial, industrial, metal and post/frame buildings, along with many other DIY applications. When you think of insulation, you should think of InfraStop®. Our products are recognized for their thermal performance, easy installation, versatility, price and environmental friendliness.


  • Easy to handle and install
  • Convenient roll sizes
  • Class A / Class 1 Fire Rating
  • Inhibits dew point condensation
  • Vapor retarder (0.02 perms)
  • Does not compress, collapse or disintegrate
  • Non-toxic / non-carcinogenic

Testing and Certification

InfraStop® products are thoroughly tested at either nationally approved independent laboratories or leading universities. Tests are performed to current American Society of Testing and Materials (ASTM) standards when a standard exists. For a copy of an actual test report, please e-mail us at

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