Roof Coatings Articles

SPF Roofers Extend Life of Historic Mississippi Skyscraper

Photos courtesy of Pro-Seal, LLC
Vendor Team

GE Silicones
Coatings manufacturer
9930 Kincey Ave.
Huntersville, NC 28078
(877) 943-7325

Intech Equipment & Supply
Equipment supplier
1921 W Grant St.
Phoenix, AZ 85009
(602) 257-0720

Lapolla Industries
Coatings and SPF manufacturer
15402 Vantage Pkwy. E #322
Houston, TX 77032
(281) 219-4100

Mattiace Company
Coatings client
125 S Congress St., Ste. 1800
Jackson, MS 39201
(601) 352-1818

Pro-Seal, LLC
Coatings and SPF contractor
P.O. Box 3371
Ridgeland, MS 39158
(601) 526-4141

Spray Foam Equipment & Manufacturing
Equipment manufacturer
1705 Beulah Church Rd.
Calhoun, LA 71225
(318) 644-5140

The Toro Co.
Equipment manufacturer
8111 Lyndale Ave. S
Bloomington, MN 55420
(888) 552-5153

Built in 1924, the Lamar Life Building is the oldest skyscraper in downtown Jackson, Mississippi, sitting directly across the street from the Governor’s Mansion. Even today, it remains Jackson’s eighth-tallest building and is listed on the National Historic Register.

But after nearly 100 years of use as an office building, real estate owner Mattiace Properties figured it could use a facelift, including a plan to transform it into a multi-use complex with luxury lofts up top and retail space down low.

“The building is being converted into luxury condos and has been completely gutted down to the walls,” said Tyler Avery, vice president of nearby insulation contractor Pro-Seal, LLC. “Contractors are doing everything from waterproofing, roofing, masonry repair, plumbing, HVAC [heating, ventilation, and air conditioning], and far more. The interior will be brand new while maintaining the historical outside.”

The SPF Makes History

Based on a desire to maintain the historic stone exterior, developers needed even more insulation up top, which made a spray polyurethane foam (SPF) roofing system attractive. “They know it’s an old building; they can’t get more insulation in the walls, so they were trying to get it as airtight as possible on top and get as much insulation as they could,” Avery said.

Pro-Seal was the sole roofing contractor chosen for the job, which took place over several months in mid-2018 and included installing an SPF and silicone coating system for the 30,000-square-foot (2,787.1 m2) flat roof and balconies. Based on the project’s broader scope, coordination and teamwork with other trades proved essential.

“It was a staged project,” Avery explained. “As they’d do prep for a section on the interior, we’d do the roof above that so that they could [install] sheetrock and do everything else. They wanted it to be watertight, but they needed to run HVAC before we did our part. They wanted what they were about to do underneath to be watertight before they started.”

This dynamic also created a time crunch that wasn’t always within Pro-Seal’s control. “The HVAC and GC [general contractor] would cut into the roof to install units, then we would have to immediately come behind to foam in where they had cut out,” Avery said. “Several times this occurred when we’d have a turnaround for our job of less than 24 hours.”

Preparation Makes Perfect

Intricate preparation proved essential for the six-person Pro-Seal crew, starting with their ability to handle many substrates. “The roof was a mix of modified bitumen, some existing foam roofing, and a section of gravel built-up,” Avery said. “The original foam roof was done poorly. It held water, and it was so lumpy that there was ponding all over the place. The goal was to create positive drainage on all roof sections.”

To prepare each surface, modified bitumen sections were torn off to the deck and then pressure washed; gravel built-up sections required gravel removal and pressure washing; and existing foam roofs were scarified using an Intech-supplied scarifier, then swept and bagged using Toro blowers. The modified bitumen, gravel built-up, and existing foam sections were completed in April, June, and July respectively, while balconies were foamed and coated in September.

Personal protective equipment (PPE) was worn throughout, including Gorilla gloves for hand protection; 3M respiratory masks and spray suits; and fall arrest equipment, such as harnesses and safety lines when working within 5 feet (1.5 m) of the edge of any open roof areas. Safety equipment was procured from Big Rock Supply, and an Ingersoll Rand generator was utilized to power various pieces of equipment.

Spray, Brush, and Roll

Application protocols varied depending on the substrate. For gravel built-up and modified bitumen sections, Lapolla’s 3-lb. (1.4 kg) Foam-Lok LPA 3000 roofing foam was sprayed on using a PH-25 reactor from Polyurethane Machinery Corp. (PMC) and a BOSS Gen1 air purge gun from Spray Foam Equipment & Manufacturing. The foam thickness averaged 3 inches (7.6 cm) across the entire roof, which was also pitched from 5 inches (12.7 cm) to 1.5 inches (3.8 cm) to move water to scuppers or internal drains.

“We usually had one guy in the trailer, a couple guys dragging the hose, one guy spraying, and another moving spray shields," Avery said of his crew's processes. Spray shields were used due to overspray concerns. 

For each section, the foam then sat for at least two hours before crew members applied a GE Enduris seam sealant around penetrations at ~40 mils (1,016.0 microns) of wet film thickness (WFT). After allowing the sealant to cure for approximately 30 minutes, each section was finished by applying ~30 mils (762.0 microns) WFT of the GE Enduris 3500 high-solids silicone coating. The crew used brushes and 9-inch (22.9 cm) rollers from Sherwin-Williams with 0.75-inch (1.9 cm) naps to apply the silicone, since overspray concerns prompted a more direct coating application.

“The key concern was the age and architectural preservation of the building,” Avery explained. “There are very intricate details and granite stone, and it was critical to avoid damage or overspray on the surfaces that cannot be replaced. Plus, it was so high up that the wind was a challenge.”

Besides having to create pitch, the crew found out during the project that many of the drains were very slow and/or had to be reworked. “We would foam and coat a balcony, for instance, and then have rain and find out it was 3-feet [0.9 m] deep in water where the foam was watertight, but the drain was out of alignment or stopped up. We would then have to come back, open the drains, and/or coat the inside of them to prevent leaks into the wall itself.”

Nearly Open for Business

Based on interior requirements including carpeting, the revamped Lamar Life Building isn’t expected to be handed over to Mattiace until February 2019. But other than ongoing minor foam repairs as needed based on other trades (such as a different crew’s scaffolding), Pro-Seal’s work was completed by September 2018.

“There have been some minor repairs, but that’s no big deal; we expect it,” Avery said. “The feedback has been very good, and the building is watertight! If you have ponding water sitting on a flat roof, it’s going to leak. That’s just the nature of the beast. The ability to move water off the building was a big selling point.”

As such, the client’s willingness to invest in an SPF system has the historic building poised for an extended lifespan well into a second century of use.

“Part of it is education,” Avery said of convincing clients to consider SPF systems. “Foam is still new. Even though it’s been around a while, it’s still relatively new in the adoption phase. You may have a GC that’s used it before, but not a project manager. It just takes a lot of education and reminding them not to panic, and that if there’s an issue, it’s easy to fix. We’ll ride it out to the very end.”

Thanks to their work, we can safely say this crew was the building’s ride or die partner!

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