Commercial buildings often have roofing attached in one of two ways; full adhesion or mechanically. Despite there being other methods, these are the most commonly used. Both roofing attachments involve a layer of insulation under the roof and a metal deck below that fixed to the structure below. As a commercial building owner, you should understand the difference in the attachment methods, so you can match the roofing to the building value. You don’t want to pay for something you don’t really need.
Mechanically Attached Roofing
As the most popular on the market, mechanically attached roofing is used the most often in commercial roofing. These systems are quick to install and relatively inexpensive. Mechanically attached roofing is easy to inspect as the workmanship can be validated by simply verifying fastener patterns. Commercial buildings typically have a metal deck, insulation layer and then a roof on the top.
To install a mechanically attached roof, you roll down the membrane and apply screws. Screws will be driven in at the edge of the membrane, directly through the insulation boards through to the metal deck. The screws are covered with the edge of the next sheet to be rolled out in succession. The membranes are then heat-welded together using a hot-air gun to create a watertight seal. Your roofing surface will be completely flat and waterproof with no gaps.
Fully Adhered Roofing
Fully adhered roof attachments are glued directly to the insulation layer below it. The insulation boards both insulate and secure the roof to the metal deck. This method is typically more expensive and more time consuming. The large quantities of glue that are required must be applied at the same time and at the right temperature, which creates challenges. The glue needs to dry to the right degree of tackiness and then a roller is used to press the membrane to the insulation layer.
Most builders believe this option to be more resistant to leaks, but this is a common misconception. It is thought that if the water was to get through, it would travel under the membrane past the glue. However, if you are unaware of any hole, water will get under the roof and continue to pool which will degrade the glue holding the roof in place. You end up with much bigger problems as the accumulated water will spread and cause damage to a larger area of the roof.
Final Thoughts
Mechanically attached roofs are more popular but in many cases, the fully adhered version is a better fit four your building. Contact us today so we can help you determine which option will work best for your building.
