EcoFoil Floor Joist Insulation is engineered to reduce radiant heat transfer and help protect against moisture in floor systems and studded walls. Constructed with two layers of polyethylene bubble insulation bonded to reflective metalized surfaces, this material forms an effective thermal break while providing a vapor barrier when seams are sealed. With 96% reflectivity and only 4% emissivity, it minimizes the amount of radiant heat that can pass through the assembly.

Designed specifically for framing spaced 16" on center, the 16" wide insulation fits neatly into joist and stud cavities. Each edge features a 3/4" staple tab, making installation fast and secure without additional trimming. Its lightweight construction also allows for easy handling in tight underfloor areas.

Effective Radiant Heat Control for Floor Systems

This reflective insulation helps block radiant heat rather than absorbing it, supporting year-round comfort and improving the performance of traditional insulation materials. Whether used in basements, crawl spaces, or between conditioned and unconditioned floors, it adds an extra layer of thermal protection.

Moisture Management & Vapor Barrier Performance

When all seams and joints are taped, the insulation acts as a continuous vapor barrier, helping reduce condensation that can lead to mold or structural issues. Pairing this product with conventional insulation is recommended when a specific R-value is required for code compliance.

Key Features

• Double-bubble core: Creates a built-in air space to reduce radiant heat transfer.
• 96% reflective surface: Only 4% of radiant heat passes through the material.
• Vapor barrier when taped: Helps prevent moisture buildup and condensation.
• Made for 16" on-center framing: Fits between floor joists or stud walls without modification.
• Easy installation: Lightweight with 3/4" staple tabs on both sides.
• Enhances insulation systems: Works alongside traditional insulation to meet required R-values.
• Ideal for crawl spaces & basements: Adds thermal protection to areas prone to heat loss.