Roof Deicing Under Membrane Roof Covering Materials
By Steven D. Bench
Managing Member, Heatizon Systems
Heatizon Systems makes roof snow melt and deicing products that utilize one of two different heating elements, Tuff Cable or ZMesh. Tuff Cable, a copper cable surrounded by an insulator which is surrounded by a jacket, is designed to be utilized in a Heatizon Heatsink Kit under medal and other electronically conductive roof covering materials. ZMesh, a bronze product that is approximately 1/16th of an inch thick, is designed to be installed under non-conductive roof covering materials such as composite, shake, asphalt, and fiberglass shingles as well as membrane roof covering materials.
In the testing performed by Intertek Testing Services N A Inc., immediately prior to ZMesh receiving its listing to UL Standards and CSA regulations, it was noted that ZMesh, when surrounded by insulation on all six (6) sides, reaches a temperature of approximately 125 degrees F at normal operating conditions. Of course when melting snow and ice off of roofs ZMesh is not surrounded by insulation and the roof temperature at the time the ZMesh is energized is typically be between 30 and 38 degrees F resulting in an expected operating temperature substantially below 125 degrees F. In the event the roof covering manufacturer establishes a particular maximum exposure temperature for his product that is below 125 degrees F it is very easy to control the maximum temperature achieved by the ZMesh using a temperature probe that shuts the system off in the event ZMesh exceeds the maximum set point.
When selecting which roof covering materials may be put over ZMesh it is important to obtain answers the following questions:
1. Will the roof covering material, and any adhesive material or technique required to attach it, be adversely affected by the alloy bronze?
2. Will the roof covering material and any adhesive material or technique required to attach it, have an adverse affect on ZMesh?
3. Can the roof covering material withstand a temperature below it equal to 125 degrees F? If the answer is no then a temperature sensing device must be utilized to establish an upper temperature shut off.
4. What is the R-Value of the material under the ZMesh?
5. Is the R-Value of the material under the ZMesh greater than the R-Value of the roof covering material?
Over the past eleven years, ZMesh has been successfully installed and operated under many projects that have also utilized membrane roof materials. These projects include the Ramirez Home is Salt Lake City, UT, the Post Office in Ketchum, ID, and Sarnafil’s membrane roof covering manufacturing facility in Canton, MA.
In the event you need additional information of Heatizon Systems ZMesh roof snow melt and deicing products please do not hesitate to contact us.
For additional information on Heatizon Systems products please visit www.heatizon.com