When David Lamouranne of GreenStar Roof Coatings landed the job of applying a new coating system to the roof of a private hangar at the New Orleans Airport, he jumped at the opportunity. While he knew the high-profile job would present some very real challenges — high winds, air traffic, and airport safety requirements — he was excited to offer his client, Atlantic Aviation, a new roof that would be green, durable, and reduce energy costs. 

The project is on the private hangar for Entergy, an integrated energy company. In addition to using the hangar for aircraft, the building also houses offices, which are attached to the front of the facility. According to Lamouranne, the 42,142-square-foot (3,915.1 m²) metal, standing seam roof was in good shape, especially considering the constant exposure to wind and other extreme weather conditions. 

“This project is a great example of a roof being re-done before it was covered in rust and needed a great deal of repairs. Atlantic Aviation didn’t have to spend any additional money repairing the metal substrate and encapsulating the area with a rust primer. They did a great job of staying ahead of everything from a preventative maintenance standpoint,” said Lamouranne.

The crew did have to fix fasteners, tighten the rake trim of the metal roof, and repair any seams that had experienced wind lift. “The great thing about the ASTEC Re-ply Roof System that we used on the hangar roof is that it goes down seamless so wind lift will no longer be an issue,” said Lamouranne — definitely a must in New Orleans. This system was also chosen because it is a green coating that will reduce energy usage and costs.

Blowin’ in the Wind
With 40-mile-per-hour (64.4 km/hr.) winds to contend with, overspray was a major concern for the crew, but the ASTEC materials were to be spray-applied, so the team constructed windscreens with polyvinyl chloride (PVC) pipes, visqueen, and tarps. Even with the severe wind that plagued the crew on most days of the job, Lamouranne is proud that because of the wind screens and the extreme caution exercised when spraying the coating material, there were no overspray problems.

In addition to the extremely windy conditions, the crew also had their hands full dealing with the air traffic on the tarmac. Although the hangar doors were closed during the coating application and the Entergy planes were safely housed inside, the airport was still very much in operation.  “There were planes coming and going everywhere — taxiing, taking off, landing. There were many times when we had to stop just to ensure that no overspray was accidentally carried off into the jet engines,” reported Lamouranne.

Hot and Steamy
Prior to the application of the ASTEC Re-ply Roof System, the GreenStar Coatings team steam cleaned the roof area using a trailer-mounted pressure cleaning system provided by John Henry Enterprises. “It is an eight-gallon-a-minute [30.3 L/min.], 24-horse power cleaner with a diesel boiler that provides steam to remove all grease, grime, and other contaminants from the roof. We like to use steam to guarantee a deep, powerful clean,” stated Lamouranne. According to Lamouranne, the specific steam cleaner he and his team used is a concrete surface cleaner that has been modified for use on metal roof surfaces.

Sealing It Up
Once the roof was cleaned, the team sealed all ridge caps with spray foam.  “We sprayed three inches [76.2 cm] of Versi-Foam into the peaks of the roof area to fill in any space where air could get in,” explained Lamouranne.  After this process, the crew was ready to apply ASTEC Surface Conditioner #4000 as an adhesion primer to the entire roof area. This coating is a concentrated aqueous acrylic emulsion sealer that is formulated to provide a monolithic surface for bonding subsequent coating layers. The crew used Graco 850 airless sprayers to apply the coating at an average thickness of two mils (50.8 microns).

With the primer laid down, the crew taped all seams with four-inch (101.6 cm) tape and spray-applied two coats of ASTEC Waterproof Sealer WPM #9 at a wet thickness of approximately 10 mils (254.0 microns) each. This fluid-applied membrane encases all roof seams and fasteners inside a tough yet pliable seamless surface. “We then went back and encapsulated all fasteners and seams with another layer of WPM #9.  For this part of the process, we used our proprietary and patent-pending system. This special tool allows applicators to lay down the proper thickness over fasteners and seams from start to finish. It allows for better quality control than the use of brushes and saves a great deal of man hours,” stated Lamouranne.

Extra Training
Lamouranne is the first to admit that it was a tough process obtaining the proper qualifications to do work at the airport. He and his team took safety training courses to drive on the airstrip without an escort. “Every year, we need to take continuing education classes and be retested so that we can do coatings work at the airport,” Lamouranne explained. In addition to these extra safety requirements, the crew was also extremely cautious when cleaning and coating up on the roof. The crew wore fall protection when 10 feet (3.1 m) from any edge. “Although the OSHA [Occupational Safety and Health Administration] guideline is that harnesses must be used and the crew must be tied off when six feet [1.8 m] from any edge, we took extra precautions,” stated Lamouranne. He adds that the roof pitch was a 1 on 12 pitch, so slope was not a safety concern.  The crew also wore tinted glasses and gloves for the duration of the job.

Green Finish
Once the roof was encapsulated with the WPM #9, it was wind and water proofed and ready for the finishing layers that protect it from ultraviolet (UV) rays, heat, and airborne corrosives. The ASTEC #2000 Finish Coat was spray-applied in two coats for a total approximate thickness of 16 mils (406.4 microns) dry.  As stated by Lamouranne, the ASTEC #2000 is a white coating that has proprietary ceramic formulations that enhance the elastomeric coating’s ability to withstand exposure to heat, UV rays, and abrasion. “It also reduces thermal shock damage because of its flexibility and is highly reflective. It is a green coating that will save Atlantic Aviation a great deal of money on energy costs, which in turn is good for the environment as well,” stated Lamouranne, adding that the ASTEC system meets standards for cool roof credits and incentives and is backed by a 10-year warranty.

The four-man crew worked for four weeks to complete the work on schedule.  “We worked seven days a week to make sure we finished within the timeframe that was required,” said Lamouranne. 

All in all, Lamouranne is pleased with the outcome of the job, and with how well his crew worked to get the job done right and on time. “With the hard work of the crew and the green coating materials from ASTEC, everything went just as it should,” said Lamouranne.