Making the most of mod bit – Part 2

By Mule-Hide Products. 

Understanding the different mod bit attachment options available. 

Modified bitumen (mod bit) roofing systems come with no shortage of benefits. From incredible toughness and durability to economical maintenance and instillation costs, it is a great low slope roofing option. Furthermore, there are a wide variety of cap sheet and attachment methods that allows mod bit to work for virtually every low slope roof out there. In the first part of this series, the experts at Mule-Hide Products looked at those cap sheet options, APP and SBS in particular, to help you identify which one is right for your project. In this article, we will cover some of the attachment methods that are out there! 

Four attachment methods 

Mod bit cap sheets can be self-adhering, torch-applied, attached using a cold-process adhesive or mopped in with hot asphalt. Adhesive and asphalt installations are messy, are often smelly, require a well-trained crew to complete them properly and, in the case of asphalt, involve having kettles of hot asphalt on the roof. 

The focus here will, therefore, be on the far more installer-friendly self-adhering and torch-applied systems. Each has advantages and characteristics that make it ideally suited to certain applications. This article will discuss self-adhering systems and a future article will address torch-applied systems. 

Self-adhering cap sheets 

Self-adhering mod bit cap sheets go on quick, clean and torch-free. They have an aggressive adhesive on the bottom and an APP or SBS weathering surface on top. Simply position the sheet, let the membrane relax, peel away the release liner, press the membrane into place and roll the membrane to ensure adhesion. 

Any torch-applied roofing installation comes with an inherent risk of fire. Self-adhering membranes eliminate that risk, making them ideally suited for projects in which that risk is unacceptable. For example, when reroofing an occupied building with a wood roof deck. They also are the perfect solution in the growing number of communities that have banned the use of torches on rooftops. 

Self-adhering membranes are installed using roofing knives, brooms, trowels, rollers and other tools and equipment that are inexpensive, readily obtained and easy to use. There is no need to purchase – and then become proficient in the proper use of – heat welding equipment. 

Careful attention must be paid to the thermometer during installation of any mod bit system, but particularly when working with self-adhering membranes. When asphalt products get cold, they become less pliable and their ability to retain tack lessens. Therefore, self-adhering mod bit cap sheets should only be installed when ambient temperatures have been at least 40 F and rising for 48 consecutive hours. The rolls themselves must be room temperature – between 60 F and 80 F – at the time of application and must not be stored outside overnight in cool weather, so having a heated storage area on site is recommended during cold-weather work. 

These temperature-related considerations mean that, in many parts of the country, self-adhering modified bitumen membranes are best thought of as a three-season solution that can be used roughly six months of the year. But when the weather is right, they are a quick, crew-friendly option that keeps torches off the rooftop. 

Keep an eye out for the third and final part of this series to learn more about the mod bit attachment options available! You can also learn more about Mule-Hide Products modified bitumen systems here. 

Original article source: Mule-Hide Products