Guide To Thermal Shock On Commercial Roofs

Guide To Thermal Shock On Commercial Roofs

23 August 2021
 Categories: , Blog


Thermal shock can cause severe damage to a membrane roof. Often, the damage seems to occur with no warning. The building may seem fine in the evening, but the next morning, there is visible damage and possibly even water leaking into your building. 

What Is Thermal Shock?

When temperatures change rapidly and drastically, thermal shock becomes a concern. The quick expansion and retraction of membrane roofing materials can lead to stress on the membrane itself. 

Certain parts of the membrane will be more prone to thermal shock. Areas with seams, such as where two lengths of membranes are sealed together, are especially at risk. Flashed and sealed spots on the membrane around rooftop vent stacks and other protrusions can also be susceptible to damage. Yet, even large expanses of the solid membrane can rupture due to thermal shock, particularly if there is standing water on the roof that may freeze.

How Does Damage Present?

The most obvious damage is a split in the membrane. Often, there are multiple splits across the surface of the roof, particularly in areas where water tends to collect. The roof membrane may also separate at seams or pull away from rooftop protrusions and appliances.

In some cases, the shock also affects the insulation and substrate beneath the roof. It may warp and push upward in response to rapid temperature changes. This gives the roof a wavy and uneven look. Water will also come in through damaged areas if the weather has been wet. 

Are There Repair Options?

In many cases, the roof can be repaired. Your roofer will make relief cuts in the insulation and substrate to relieve the pressure that caused buckling. Any wet or damaged insulation will be removed and replaced. The final bit of work on the substrate is to level it completely so that membrane repair can take place. Drains may also be cleared so that water drains more readily, which will help reduce the chances of future thermal damages. 

If there are only a few split areas or pulled seams, your roofer can patch and reseal them. If extensive damage has occurred, though, then they may need to remove the old membrane and replace it with a new one. Once properly sealed and stretched, this new membrane should be able to withstand thermal shock in the future. 

Contact a commercial roof repair service, such as Tectum Roofing, if you notice thermal shock damage on your roof.