Each year, commercial roofing systems across Boise, Idaho are exposed to weather extremes of one type or another. Because the roofs of most business establishments are either flat or low slope, they must endure much more of what Mother Nature throws at them than their residential equivalents. And if it’s not the thousands of extra pounds of weight from snow in the winter, it’s the blistering heat of summer.

Speaking of blistering, if you are a business owner that has been up to your roof lately, you might’ve noticed what looks like actual blisters in your roofing system’s paint or top layer of protective coating. Now that the temperatures are rising, your roof’s temperature on a hot, sunny day can reach excessive temperatures depending on the color and material is it surfaced with. For example, a black roof can reach 190˚ F, a white roof will most likely reach at least 120˚ F, and a gravel-topped roof might top out at somewhere in the middle at 145˚ F.

As your commercial roofing materials heat up to those temperatures, pressure between the layers of your roof builds up, causing the adhesive to weaken and allow pockets of air to expand, creating the “blisters” you see forming on your roof. Because the protective membranes on most flat or low-slope roofs have a high elasticity, slight blistering is not generally a great cause for concern initially. It is important to note though, that stepping on even small blisters should be avoided when walking on your roof during inspections. Crushing just one of the blisters can compromise your roof’s watertight seal, leading to costly damages down the line.

If the same spots routinely experience significant blistering, however, the membrane can become damaged and leave your roof and sub-roof open to larger issues related to water damage from leaks. It is a generally accepted industry standard that when blisters approach the 2-foot mark in diameter, professional commercial roofing contractors should be called in to evaluate the potential damage and recommend necessary repairs.

Although in most cases of smaller blistering of the elastic membrane will remain watertight, however, paint or protective coatings over it will most likely show cracks. For the larger blisters, the pros will attempt to discern whether water infiltration has taken place. If necessary they will remove and patch the roof in that area. They’ll also remove any wet insulation and decking materials before patching with all new materials, including a new section of membrane.

Here in Boise, Idaho we have a fair share of extreme weather that can significantly affect your commercial roofing systems if they are left unchecked. Regular visual inspections throughout these next few hot months can help to identify potential problem areas affected by blistering. Don’t wait until you already have a problem to get up on your roof – being proactive in your roof maintenance now could save you tens of thousands of dollars in repair costs later on.