Problem Solving Forum
September 8 - September 12, 2014
Where there is likely to be ponding water, what generic type of reflective roof coating will work best, and why?
Selected Answers
From
GENE ROCKMAN of CFR LLC on
September 16, 2014:
I have tried to find the best with easy installati ...read more
I have tried to find the best with easy installation. I found EPDM liquid rubber to be my choice to stand up to ponding water. The system is basically 3 steps: clean, prime, and, in your case, apply a top coat of EPDM liquid rubber. You can get a 3-year warranty if you do it yourself or up to 10 years with an authorized installer. It can then be recoated to extend the warranty if needed.
From
Jeff Edson of EcoBiz on
September 10, 2014:
Please search silicone coating permeability and yo ...read more
Please search silicone coating permeability and you'll find an article from Paint & Coatings Industry magazine submitted by Wacker Silicones, a leader in silicone technology. It says silicone- based finishes offer two major benefits, "outstanding water vapor permeability and low water absorption."
From
John T. Hull of Sherwin-Williams on
September 9, 2014:
Be careful with silicones over known ponding areas ...read more
Be careful with silicones over known ponding areas. Silicones have near zero permeability, so they will not breathe. This, in turn, can lead to blistering on the exterior and possibly reduced air quality on the interior. A better method is to use tapered insulation boards to create positive drainage and eliminate the ponding altogether.
From
Jeff Edson of EcoBiz on
September 8, 2014:
Silicones are virtually unaffected by ponding wate ...read more
Silicones are virtually unaffected by ponding water and UV exposure due to their inorganic nature.
From
Jack Smart of John Smart Consulting Engineers on
September 8, 2014:
I have a mansard roof on my house with multiple fl ...read more
I have a mansard roof on my house with multiple flat sections. A previous asphalt roof failed in five years at a seam in a ponded area, conveniently occurring just months after the gaurentee and causing extensive interior damage . It was replaced with a a light grey membrane roof which is working very well. It is also possible to put foam boards under the membrane to greatly reduce the volume of water which collects in ponds, which also greatly reduces the load on the roof after a rain. Because the membrane is so light-weight, we left the old roof in place and we definitely notice a cooler house.