Cool white roofs: Commercial metal roof repair

This aging aluminum roof over a glass manufacturing center received the cool roofing system.
Over the previous 20 years, isolated repairs were performed and were quite successful due to the rust-free panels.
Nevertheless, the original installation of these aluminum panels presented difficulties for maintaining a leak-free roof.

Metal roof exhibited numerous problems

Adhesive missing in panel overlaps
Open drill holes for fasteners
Cheap metal sheets bent to make a ridge cap
Large AC unit for office located on roof
Missing end closures around roof edges

After the turn of the century, the stars aligned in the cosmos auspiciously, thereby encouraging company management to address the roof repairs as a comprehensive project.

The crew cleaned the roof with pressure washers.  Then they began the important portion of the project: repair of all panel overlaps. The panel overlap repairs, or seaming as crew members call this work, employ rolls of mesh and roofing acrylic. The mesh is cut to a width that covers the overlaps and the fasteners both.  Usually the rolls are cut at the acrylic manufacturer's site, but on this project, the unusual patterns of the original installer called for a quick width adjustment.  There is a reason my crew chief packs a machete in the truck.

Seaming is performed on both the horizontal and vertical seams. The horizontal seams are somewhat tricky to properly weatherproof. As a photo shows below, a quick application of mesh and acrylic will result in gaps between the materials and the metal panel profile. Years of experience by my crew correct these rookie mistakes.

Most metal roofs require a primer, but the aluminum panels here were virtually rust free. The ridge cap and some flashing did require strong primer applications.

Metal roof ridge cap repair

As the top three photos illustrate, mesh is used to reinforce the end closure areas. The mesh is placed in a manner that allows movement and security against blowing rain problems.

AC unit on metal roof

Of course, a large AC unit for the office center is located directly over the principal company manager's office. And, of course, the AC repairmen weigh in at 300 lbs. The result is a trampled metal panel area near the AC unit.

In this AC area, the fully reinforced technique was used, similar to our work on historical metal panels dating back to the late 1800s.  Instead of just seaming panel overlaps, this reinforced method covers the entire metal panel...a carpet for the AC repairmen.

White acrylic coatings

After the repair work, the crew brushed down two coats of white acrylic. Although it is tempting to spray, thereby reducing the crew's time at the site, this project strongly suggested a mechanical application over every inch would be desirable. The original installer's workers exhibited different fasteners and drilling habits. My crew chief became so familiar with this roof, he could identify metal panels installed by the same worker from the original building's construction.

As you can see from the photos, the mesh repairs are buried in several layers of acrylic, thereby virtually eliminating any chance of leakage.

Because the building lacks air conditioning, the white roof allows the coolest possible interior for this company's workforce during the summer months.

Are you looking for a cool roof contractor?

If you are seeking an experienced company to offer an estimate to preserve your existing metal roof and transform it to a cool roof, one of us would be delighted to visit your site, discuss the alternatives available and, if requested, submit a quote for converting your metal panels to a cool roof. Click here for a map of our geographical work area.

Beyond information about our contracting services, this site is designed for individuals interested in cool roofs and vintage metal roofing--photos, technical tidbits and history. These web pages are prepared by the same contractor that specializes in the restoration of these metal roofs.  She enjoys dabbling in website construction, therefore photos and articles are simply presented.   All pictures are from Roof Menders projects, the same contractor.  If you have questions, just call 610-941-1051 for a chat.