Radiant Barrier Information

Understand how radiant barrier works, choose the right material for the assembly, and find the installation and specification resources for your project.

Start here

What Is Radiant Barrier?

Learn what radiant barrier does, why at least one of its two reflective faces needs an adjacent air space, and where it fits alongside conventional insulation.

Read the overview

Building science

How Radiant Barrier Works

See the difference between radiant, conductive, and convective heat transfer and how a low-emittance surface changes radiant heat flow.

See how it works

Planning

Performance & Savings

Review the project conditions that affect results, including climate, duct location, existing insulation, air space, and installation quality.

Review performance factors

Architects & specifiers

CSI Specifications

Access the three-part CSI guide specification with Ra-flect Radiant Barrier as the Basis of Design. A free account is required for downloads.

Access specifications

Project planning guides

Attic projects

Radiant Barrier for Attics

Understand placement, air spaces, ventilation, dust, and roll-width selection for existing homes.

Read the attic guide

Budgeting

Radiant Barrier Cost Guide

See how roof area, pitch, overhang, shipping, roll width, and installation method affect project cost.

Plan the budget

Comparison

Radiant Barrier vs Insulation

Learn which heat-transfer mechanism each material addresses and why many attics use both.

Compare the materials

Climate

Hot and Humid Climates

Plan a breathable radiant-barrier installation without blocking attic ventilation or drying paths.

Read the climate guide

Sizing

How Much Do I Need?

Calculate roof coverage from footprint, pitch, overhang, and waste, then choose efficient roll sizes.

Calculate coverage

Commercial projects

Metal Buildings

Coordinate reflective air spaces, condensation control, and LP or VB selection for metal construction.

Read the metal-building guide

Choosing LP or VB: Laser Perforated (LP) is the safer default for most vented attics and breathable assemblies. Vapor Barrier (VB) is non-perforated and is intended for assemblies where vapor control is a deliberate design requirement. Compare available rolls.

Plan the next step

Use the installation library for project-specific methods, browse common questions, or request a material sample before ordering.

Plan your order

Ready to size your project?

Laser Perforated (LP) is the safer default for most vented attics and breathable assemblies. Choose Vapor Barrier (VB) only when non-perforated vapor control is an intentional part of the design.