Do-It-Yourself (DIY)
Cathedral Ceiling



Northern Zone of the USA - With Reflectix® Below the Mass Insulation

R-7.0 Summer & R-1.0 Winter and a Vapor/Moisture Barrier

Southern Zone of the USA - With Reflectix® Above the Mass Insulation
R-6.0 Summer & R-2.0 Winter or a Radiant Barrier - Blocks 94% + Radiant Heat

In a Cathedral Ceiling, several installation options are available for enhancing the energy efficiency of this type of structure. Ease of installation and handling are additional benefits that make adding Reflectix® to your project attractive. There are two methods for installing Reflectix® products in a Cathedral Ceiling. Depending on the region of the USA your home is located, please refer to the “Zip Code Zone Locator” on this page.







Recommended Products:

Double Reflective Insulation
Reflective/Bubble/Bubble/Reflective - Roll
• BP24025 (24” x 25’)
• BP48025 (48” x 25’)
Staple Tab, Reflective/Bubble/Bubble/Reflective - Roll
• ST16025 (16” x 25’)
• ST24025 (24” x 25’)
Radiant Barrier
Radiant Barrier, Reflective/Woven Fabric/Reflective - Roll (Heavy Duty)
• RB4812550 (48” x 125’)
Note: Click here for information on our larger rolls which are available by Special Order at the Contractor or Customer Service Desks.

Benefits:

• Easy to install
• Does not require any protective garments or respirators
• Convenient roll sizes
• Does not promote growth of mold or mildew
• Not affected by moisture or humidity

Testing and Certification:
Reflectix® 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. To obtain a copy of our Product Testing Specifications, please refer to our website “Literature Tab” above. The documents are also available by e-mail at customerservice@reflectixinc.com or call 800-879-3645.

Air Space Requirements:
Zip Code Zone Locator

For the Regional Recommendation for the Cathedral Ceiling application, please verify the location of your home with the “Zip Code Zone Locator” function below.

Federal Trade Commission Fact Sheet: Reflective Insulation
Installation Instructions: (There are 2 options)

Download DIY Cathedral Ceiling Installation Instructions 1114.pdf

1. Directly to Roof Deck - Above Fiberglass - Southern Zone of the USA Only (Refer to "Zip Code Zone Locator" Above)

• Benefit - R-6.0 Summer & R-2.0 Winter
• It is easiest to install either 16” or 24” wide product (depending on rafter spacing).
• Begin at the top of the cavity. Run product flush to the decking, parallel to the rafter.
• Staple sheet directly to the deck (Nails poking through the Reflectix® product from above will not interfere with performance).
• Do not block any venting (cut around).
• No need to cover rafters (no loop around).
• Ensure that a continuous air space (0.75 inch minimum) is on the bottom side of the Reflectix® product (required and for ventilation).
• Install venting and mass insulation per local codes and manufacturer’s installation instructions.

2. Attached to the Lower Edge of the Rafter - Below the Mass Insulation (Fiberglass) - Northern Zone of the USA Only (Refer to "Zip Code Zone Locator" Above)
• Benefit - R-7.0 Summer & R-1.0 Winter and a Vapor/Moisture Barrier
• Either the 16” or 24” wide product (depending on rafter spacing) is recommended.
• The Staple Tab product is the easiest to work with for this application (but the Standard Edge product is equally effective).
• Install venting (required in Cathedral Ceilings) and mass insulation per local codes and manufacturer’s installation instructions.
• A minimum of a 0.75” air space is required on the underside (towards the interior of the home) of the Reflectix® product. This air space can be created in one of two installation methods:
1. Tuck the product up into the cavity and staple to the side of the rafter every 2 to 3 inches fully enclosing the rafter cavity.
2. Staple the product directly to the underside of the rafter every 2 to 3 inches fully enclosing the rafter cavity. Nail 1” x 2” (nominal) furring strips to the underside of the rafter (creating a continuous 0.75” cavity).
• Install interior panel per local codes and manufacturer’s installation instructions.

Reflective/Woven Fabric Radiant Barrier
Installation Instructions:

Download DIY Cathedral Ceiling Installation Instructions 1114.pdf

Directly to Roof Decking - Above Fiberglass - Southern Zone of the USA Only (Refer to "Zip Code Zone Locator" Above)

• Benefit - Radiant Barrier - Blocks 94%+ of radiant heat
• Cut the entire roll of product into 16” or 24” lengths with a miter saw (depending on rafter spacing).
• Begin at the top of the cavity. Run product flush to the decking, parallel to the rafter.
• Staple sheet directly to the deck (Nails poking through the Reflectix® product from above will not interfere with performance).
• Do not block any venting (cut around).
• No need to cover rafters (no loop around).
• Ensure that a continuous air space (0.75 inch minimum) is on the bottom side of the Reflectix® product (required and for ventilation).
• Install venting and mass insulation per local codes and manufacturer’s installation instructions.

Ventilation:
Good ventilation in your attic increases your comfort and helps the materials of your house last longer. Be sure not to block ventilation paths when you install Reflectix®.

Important:

Additional Resources:
Zip Code Zone Locator
This function provides regional installation recommendations for the following applications: Attic & Cathedral Ceiling
Submit
DIY Product Calculator Type:
Roof/Attic Application: Radiant Barrier Locate a Retailer
0 sq. ft. of roof/attic area 0 rolls
*Note: This calculator is for the convenience of our customers. These recommendations are for approximate product quantity.

Video Library:

For additional videos, click here.
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