It’s a human primary need to have a roof over one’s head. It gives us shade when the sun is high, keeps us dry when the rain pours. In some parts of the world, roofing has to withstand other threats like blizzards, heavy snow, and the occasional hailstorm. Hail is not the most destructive weather condition. But the damage it does on roofing can go undetected. What appears to be small cracks on shingles could be hiding something worse below.
As far as our roofing went as time went by, we moved on from straws and wood. Then, we used stones, metal and synthetic materials such as EPDM roofing.
What is EPDM?
EPDM stands for “Ethylene Propylene Diene Terpolymer”. It’s a kind of elastomeric polymer, aka rubber, synthesized from Ethylene, Propylene, and a bit of Diene Monomer. Combined with an array of stabilizers, processing oils, and carbon, we have the makings of a tough rubber coating meant to take on the harshest everyday impacts.
The rubber sheets can be installed on roofs in many ways. It could be glued to using any strong adhesives, machined in, or simply ballasted. The width of the rubber can vary per order, but it comes in two fixed thicknesses, 45 mm and 60 mm. They normally come in black or white, but other orders can be made with custom colors.
Apart from roofing, EPDM sheets are also used in making pond linings, any surfaces that need waterproofing, and occasionally, flooring and walls. It doesn’t need any maintenance or special coating to keep it strong. It’s basically a place and forget roofing.
After proper installation, EPDM roofing can last for up to 30 years. It can even withstand intense heat and cold that would normally cause rubber to go brittle and crack. It’s resistant to UV rays, sudden thermal spikes, heat and cold cycling, and most importantly, resistant to hail.
EPDM vs Hail
Big chunks of ice falling from the sky is a force to be reckoned with. Ice formed in thin air is stronger than ice you can make in your freezer. EPDM is essentially an exceptionally durable rubber sheet. This means it can absorb a significant amount of shock. Even in cases where the hail chunks are as big as tennis balls, EDPM will absorb most of the impact, especially the thicker 60 mm sheets.
What you need to watch out for, is EPDM roofing that’s past its guarantee. EPDM guarantees often last 15-30 years. But, older EPDM roofings have cracks and areas of expansion called “tents” that can become point-of-failures. After a hail storm, you could see small tears and spider-web cracks. This makes the material under the roof vulnerable to damage. When you see tears or cracks on EPDM roofing, make sure to check what’s under. If it wasn’t able to absorb the full impact, it’s very likely to transfer that impact to what’s under it.
On EPDM which are 15 years and younger, you shouldn’t expect any damages. There may be small tears less than a centimeter deep, which can be mended with special tape or adhesive.