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74 JANUARY 2017 COATINGSPROMAG.COM said. "Specifically, we let them know we were prepared to move around so we weren't working directly above their heads while they were at home." With the schedule coordinated in advance as much as possi- ble, the crew began at 8 a.m. sharp the next day by laying down padded protective plastic floor coverings between the loading ramp and passenger elevator, inside the passenger elevator, between the passenger elevator and roof access stairs, and on all landings in between. ey also padded the elevator walls. Unfortunately, over the course of this 90-day project, the crew got very used to this procedure, because every day at 5 p.m., all such padding had to be removed. e first order of business was to water blast the roof using their 2,500 psi (17.24 MPa) Craftsman pressure washer. With that underway, Gonzalez formulated a plan to partition the work. Since the roof 's four cylindrical towers jutted up from the main roof, his crew would do those first to avoid risk of marring areas adjacent to the towers when they later applied the main roof topcoat. Wishing They Could Hover Tiptoeing as quietly as possible, wishing they could hover, the FQR crewmen donned knee pads, Ty vek suits, and 3M respira- tors when necessary. ey started off with utility knives to cut out waterlogged BUR sections down to the concrete substrate. W hat they found was approximately 3 inches (7.6 cm) of polyisocyanurate insulation, a layer of high-density wood fiber- board, and three layers of Type IV fiberglass mat topped with a modified bitumen cap sheet. "Working above these penthouse ceilings was tricky," said Gonzalez. "W here we had to remove wet areas was the most intrusive part. ere is no quiet way to remove a BUR from any substrate, but thankfully the material was glued to concrete rather than nailed to wood, so there was no loud nail yanking but slightly quieter scraping of the deck." After replacing the waterlogged sections of BUR (with like materials), the crew focused on the labor-intensive process of lugging cans of silicone roof sealer up to the worksite. ey used hand trucks to move the cans from the loading docks, up the elevator, and to the access stairs. en they began the painful process of lugging the 5-gallon (18.9 L), 45-pound (20.4 kg) cans up four flights of stairs to the tower roof decks. e first thing to know about Pro-Grade 923 butter-grade sealer is that you don't mix it. Just pop open the cans and start spreading at thicknesses up to ¼ inch (0.6 cm), according to Henry's manufacturer's technical data sheet. Eric ompson, Henry territory manager for Florida and the Caribbean, shares a slick application tip. "For seams, scoop out Pro-Grade 923 with a trowel, spread it with a 4-inch [10.2 cm] brush, trowel again to smooth it out, and use the brush again to spread the sealer 2 to 4 inches [5.1–10.2 cm] beyond the seams," ompson said. If voids occur, Henry recommends allowing the 923 to set up (on average 1–3 hours to tack free) and coat again. Full cure typically occurs in 12–18 hours, depending upon temperature and humidity. On this roof, there were more than 100 protrusions that the crew typically brush coated up to 12 inches (30.5 cm) high. ey also had hundreds of linear feet of deck-to-parapet flash- ings to contend with. A lthough it took extra effort to apply sealer to the flashing seams, having parapet walls actually saved a bit of work. "Parapet walls are usually beneficial when it comes to safety coordination and overspray issues," said Amador. "Bella Mare has a nice parapet — about 5 feet [1.5 m] — but on buildings without them, you have to rig safety barricades, wear fall protection gear, erect overspray barriers, and shuffle vehicles, because obviously one drop of silicone on a car can be disastrous." Soar Into Action With the brunt of the detailed brush work out of the way, the crew soared into action by roller applying approximately 10 to 15 mils (254.0 to 381.0 microns) dry film thickness (DFT) of Henry's PGE966 primer to the repaired areas. A lthough project Next was the primer, Henry's Pro-Grade Elite PGE966. The crew applied 10–15 mils (254.0–381.0 microns) dry film thickness (DFT) of the primer to repaired areas, seams, protrusions, and parapet flashings using rollers. Roof Recoat In addition to coordinating schedules for the penthouse occupants, the crew also had to work around access issues. They could only use a passenger elevator bet ween 8 a.m. and 4 p.m., Monday through Friday.