Reflective Insulation, Radiant Barriers and Interior Radiation Control Coatings (IRCCs) for Use In Pre- Engineered Metal Buildings

Scope

In both the United States and Canada there is significant growing interest throughout the pre-engineered steel building industry for the application of reflective insulation materials and IRCCs in pre-engineered steel buildings. This bulletin has been prepared by the Reflective Insulation Manufacturers Association International (RIMA-I) to address applications and their performance.

Definitions:

Reflective Insulation:Thermal insulation consisting of one or more low emittance surfaces, bounding one or more enclosed air spaces.

Radiant Barrier:A reflective material having a surface emittance of 0.1 or less used for the sole purpose of limiting heat transfer.

Interior Radiation Control Coatings:A non-thickness dependent, low-emittance coating. Formulated coatings with thermal emittance less than 0.25.

Emittance:Emittance refers to the ability of the surface to emit radiant energy. Emittance ranges from 0 to 1. A lower value indicates a reflective surface with a low level of radiation.

High- Emittance Facer:White Plastic films Numbers 0.85-0.95

Low-Emittance Facer:Foil or metalized films 0.03-0.05

R-Value:Property of an insulation material used to characterize the effectiveness of the insulation in reducing heat transfer. The higher the “R” value, the better the insulation’s ability to reduce heat transfer.

U-Value: A measure of the heat transmission through a building part or given thickness of a material (as insulation). The lower the “U” value, the better the insulation’s ability to reduce heat transfer.

Types of Products

1. Foil or metallized film-faced polyethylene bubblepack reflective insulation.
2. Foil or metallized film-faced polyethylene or polypropylene foam reflective insulation.
3. Reflective insulation and mass insulation combinations (hybrid systems).
4. Interior radiation control coating (IRCC) – low-emittance coatings.

Applications

Wall Assembly: (See Drawings Appendix B in PDF)

1. Reflective insulation – Draped over purlins. One-inch closed air space facing up with an open air space below.
2. Reflective insulation – Attached to bottom of purlin. Eight-inch closed air space facing up with an open air below.
3. Reflective insulation – Installed over existing metal roof with ¾-inch spacers and new metal roof with ¾-inch enclosed air space between the reflective insulation and the roof panels.
4. Radiation control coating (low-emittance) sprayed to the underside of the roof deck.

Roof Assembly Hybrid System: (See Drawings ASHRAE Handbook of Fundamentals)

Installation

In accordance with manufacturer’s instructions. It is recommended to contact the manufacturer of the product being used for specific installation instructions.

Aesthetics and Comfort

1. Improves lighting.

Health and Safety

1. The manufacturer shall provide the users with information regarding any hazards and recommended protective measures to be employed for safe installation and use of the material.
2. Lightweight and easy to handle.
3. No itchy fibers.
4. Refer to manufacturer’s MSDS Data Sheets.

Storage

1. The material shall be stored in accordance with the manufacturer’s recommendations.