The existing roof at a popular hotel in Los Angeles was made of Steel Deck with lightweight concrete. Existing roof system was a slag rock embedded in coal tar pitch built-up system. Many of the leaks were caused by blisters and ridging in the built-up roof. Rock was washed into the drain areas exposing coal tar built-up sheets. The exposed coal tar was becoming brittle and cracking due to sun exposure.
APOC recommended that the A/C curbs be raised to create proper clearance from the roof deck. Customer also agreed to install new sheet metal pans on top of the A/C curbs before they were reset. Filled existing pitch pans with APOC #502 and #501 Neoprene to ensure there was no cracking due to possible movement.
“Another successful project with APOC. The APOC technical team was on the project every day.”
AM2-FG-MF-PE-252 Power washed existing roof after the slag rock was power vacuumed off the roof. Applied flood coat of APOC #300 asphalt emulsion over existing roof system at 9-12 g/100 sq.ft. Flood coat helps level roof where rock is not completely removed. After flood coat cures applied Monoform, 9 gal emulsion + 3 lbs chopped glass per 100 sq.ft. Let cure. Applied two layers of 40” polyester mesh, each layer set in 4 gal of APOC #300 asphalt emulsion, allowed to cure. Applied APOC #252 Sun White Acrylic coating at 3 gal/100 sq. ft. Coating applied in 2 passes at 1 1⁄2 gal per pass. Base coat was grey, top coat was white.
