DensDeck Roof Board

DensDeck Roof Board

Product Descriptive Name
Glass Mat Faced Gypsum Cover Board 
Product Short Description
DensDeck Roof Board is a gypsum cover board with a glass mat facer.

Product Details

DensDeck Roof Board

Product Long Description


DensDeck Roof Board


Meets the requirements of ASTM C 1177

Fire Performance: FM Class 1 for fire barrier requirements and UL Class A unlimited slope with excellent surface burning characteristics. 5/8" thickness meets the requirements of Type X per ASTM C 1177.

Moisture and Mold Resistance: Scores a 10, the highest performance level for mold resistance, when tested in accordance with ASTM D 3273.



Marcus High School

The Marcus High School reroof project came about because the previous system was damaged by hail. The contractor up for such a large project was Martin Tomlinson Roofing, and they installed a two ply bituminous system made by Johns Manville.

Colorado Mountain School Expansion Roof with JM EPDM R FIT

Summit High School (SHS) expanded its main building by 35,200 square feet. Arapahoe Roofing and Sheet Metal, Inc. won the job to roof this major addition. As a long-time Johns Manville partner, Arapahoe worked with the District’s facilities manager to choose a complete JM system that included 75 mil reinforced membrane as specified by the architect.

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Johns Manville offers one of the most comprehensive portfolios of commercial low-slope roofing solutions. We have a long standing dedication to providing solution-based systems for building owners.

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Here you will find quick links and cheat sheets to Johns Manville roofing systems code approvals and ratings. 

Guarantees and Roof Maintenance

Support services can include: conceptual product information, building science, wind uplift data, national and local code understanding, FM Global® and UL® regulations, fastening patterns and sheet layouts, installation guidelines and standard details.

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Re-roofing mechanically attached or ballasted insulated single-ply systems now have the potential for recycling versus contributing to a landfill.

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The Submittal Wizard is a tool to help you pull together the necessary documents for your submittal package.

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