For flat and low-slope commercial roofs, spray polyurethane foam has gained a lot of traction. Many people are interested in it because of how energy-efficient it is – with the push toward greener design, foam roofing stands out as particularly eco-friendly. And it doesn't hurt that being energy-efficient saves money.
But if you live in an area prone to high winds, severe storms, or hurricanes, none of that matters unless your roofing can withstand the elements. So how does SPF roofing hold up to extreme weather?
SPF roofs have one big advantage when it comes to high winds: the fact that they cure into one continuous piece with no edges or seams. This means a couple of important things when it comes to high winds.
First of all, a building with a spray polyurethane roof is more sound because of that roof. The roof acts to hold the entire building together, giving it resistance to structural damage like that caused by extreme winds.
Second, a major component of damage in high winds comes after a piece of a roof has been lifted away. This gives the wind a way into the building, where it gets under other pieces of roof and tears them up. As a single piece, an SPF roof doesn't give the wind any way under it, making it highly resistant to wind uplift.
When you think of foam, you might think of a soft, absorbent material – so how can it stay dry in the rain? But SPF roofs are what is known as closed-cell systems – the open areas in the foam are completely sealed off from the outside. This is what makes SPF roofs waterproof.
Another worry with storms is damage from hail or falling debris. The flexibility of the cells in a spray foam roof are part of what gives it such great impact resistance, with just enough give to not fracture under stress. The other part is in the coating – many SPF roofs are given elastomeric or silicone coatings, both of which improve impact resistance and protect the foam below.
Hurricanes involve almost every facet of weather resistance. From high winds to rain to debris, Mother Nature really throws everything she has at buildings during a hurricane. So in addition to the previously mentioned qualities of spray foam, in hurricane conditions, it's important that a roof be able to withstand large amounts of water without leaking.
Even if water pools up on the roof and can't be removed quickly, a properly installed SPF roof will have no trouble with it. Just like with high winds, the roof benefits from having no seams – there's nowhere for the water to get into. Instead, it will sit on the roof until it evaporates or is cleaned up manually.