ga('create', 'UA-16038215-1', 'auto'); ga('send', 'pageview');
Home | Commercial SPF | Restoring Bat Bridge
batbridge1

Restoring Bat Bridge

Spray foam insulation offsets danger to a protected bat species.

By Juan Sagarbarria

Bats – the blind, nocturnal majestic mammals that are loved by some and disdained by others, are actually vital components of ecosystems throughout the eastern United States and the survival and conservation of several of their species is deemed extremely important by many wildlife protection agencies. Because they are not equipped for day roaming, they secure shelter in deep, dark hideaways during daylight hours. These obscure locations, denominated as bat housing, come in different forms, ranging from caves (not unlike Bruce Wayne’s) to abandoned homes, from belfries to the underside of bridges.  It’s not rare that some of these structures are restructured or retrofitted over time, and when that happens, bats residing in these places can perish and in some instances that means that particular species of bat can suffer altogether. In terms of self-preservation, the ideal scenario is for the bats to recognize the threat that these repairs entail and relocate to other habitats before it’s too late.

This was the exact mission of Elite Insulation & PolyPro LLC (Elite), a spray polyurethane contracting company, when they completed an SPF application last year as a direct response to protecting a bat species that had been roosting in the inner chambers of the underside of the Luray West Bridge located in Page County, Virginia.

The Luray West Bridge, built in 1934 with a forecasted life span of 50 years, is scheduled for an imminent tear down and subsequent replacement with a brand new structure. With this in mind, the Virginia Department of Transportation (VDOT) requires that any bridge within range of federally protected bats be inspected for the presence of bats below the deck surface in the interest of species preservation. As it happens, the underside of the Luray West Bridge serves as the home of the federally endangered Indiana bat (Myotis sodalis), as well as the recently listed, federally threatened, Northern long-eared bat (Myotis septentionalis). Studies of the bats’ migration pattern revealed that these bats typically arrive in the spring, so the town of Luray and the VDOT looked for a way to prevent these bats from getting inside the Luray West Bridge and to instead find an alternate nesting and spawning ground. And that’s how spray foam came into the picture.

batbridge9The job itself was simple on paper: Filling the cracks and crevices on the underside of the bridge with spray foam before springtime in an effort to prevent these protected bat species from continuing to make their homes there, so that the town could then proceed with the demolition and restoration of the bridge.

Ken Wells, a veteran in spray-applied foam applications and owner of Elite, stresses the importance of completing this application while there were no bats in the vicinity, let alone inside these cracks and crevices on the underside of the Luray West Bridge.

“We needed to eliminate the homes that the bats had made underneath the bridge before they came back by spraying ‘any crack or crevice you can fit your pinky into’, as a local expert put it,” Wells says. “We needed to make sure that the bats weren’t inside the bridge while our work and the repairs were being performed. By installing spray foam to fill these cracks and crevices, we essentially protected them. They are resourceful creatures and they will find another safe place to live.”

It might have been a simple job on paper, and the job specifications only required a single set of closed-cell foam to be sprayed to these voids, covering a total of 5,000 board feet, but, notwithstanding, it required great effort and strategic planning by the Elite crew to carry out the application. The first and foremost problem of spraying foam to the underside of a bridge – how do you prevent the hose from falling into the waters of the Hawksbill Creek below?  According to Wells, it required attention to detail – and a Snooper bridge inspection truck.

The bridge inspection truck contained a boom lift, which allowed the Elite crew to park the truck on the bridge and then easily access the underside of the bridge by way of the boom lift. “The hose was tied off to the boom, so it couldn’t fall,” says Wells.

The benefit wasn’t for the bridge; it was for the protected species of bat.”

The rental of the Snooper bridge inspection truck included two operators: One to accompany the Elite sprayer inside the basket of the boom lift and a driver to position the truck according to the basket operator’s commands. Over the course of the installation, the driver and the basket operator were in constant communication so that the truck could go forward or backward whenever the Elite crew needed to access a given spray area at any particular point in the project. For added safety, there was an Elite crewmember responsible for releasing and pulling the heated hose as needed when the boom lift was moved to further prevent the hose from falling in the water. There was another Elite crewmember with a radio at ground level in charge of spotting and communicating any potential issues to the rest of the crew.

The Elite crew was in a race against time. They did not want to block the bridge from regular Luray through-traffic nor did they want to incur the substantial expense that signified an additional day of the Snooper truck rental. They only had one day and a small window of time – from 7 a.m. to 3 p.m. – in that day to complete the job. Since the traffic pattern had to be modified with the bridge inspection truck and Elite’s foam rig needing to be constantly moved, the town of Luray had requested that the Elite crew wrap up the application before out-of-school traffic ensued so that the route of certain school buses was not altered. The Elite crew posted “Keep Out” signage and taped off the entire area to halt vehicular and pedestrian access.

Full steam ahead, they prepped the area by powerwashing off lingering spider webs and guano residue around the concrete and wooden substrate. Then, the sprayer and the basket operator suited up in SafeGard coveralls coupled with PPE consisting of 3M respirators, Memphis Gloves, full-body harnesses with lanyards and high-visibility vests. The area was then thoroughly inspected for bats one last time before the spray foam application began.

Using a Graco Reactor 2 H-XP2 proportioner and a Graco Fusion air-purge gun, the Elite sprayer applied to the cracks and crevices below the bridge two inches of FOAM-LOK FL 2000, a 2 lb. closed-cell spray polyurethane foam formulated by Lapolla. Not only does the FOAM-LOK FL 2000 tenaciously adhere to framing members and dry substrates, it provides superior energy efficiency and durability while significantly reducing unmanaged moisture and air infiltration. Due to its rigid and robust properties, the FOAM-LOK effectively sealed the “bat homes” and will prevent other roosting nests from being created. In a nutshell, the bats will have to go elsewhere this coming spring. Wells pointed out that a top coat was not required because the city of Luray had requested “a quick solution that could give them long enough to tear the bridge down and rebuild.”

“The SPF was a direct solution to the problem,” proclaims Wells. “There was no other feasible way to fill these cracks such that the bats couldn’t live there anymore. The benefit wasn’t for the bridge; it was for the protected species of bat. As the core of this project was wanting to protect the bats and make sure they weren’t harmed in any way.”

The project did sustain a hiccup or two. Wells admitted that during the application, a hose heat wire coupler went bad and began to melt, warranting a quick solution to mitigate downtime.

“We shut down, diagnosed, and narrowed down the problem,” Wells points out. “We opened the hose cover, repaired the damaged coupler, and began spraying again.”

But did the crew complete the job in time? They sure did, and just in the nick of time, according to Wells. He recounts that the crew completed the application, cleaned up the site, and vacated the premises right before school dismissal, meaning the traffic pattern was restored for the school buses and no one was the wiser. Not only that, but Wells mentioned that the town of Luray and the engineers in charge of the bridge’s restoration remitted positive feedback about the performance of SPF and how delighted they were that they can now move on to the next phase of restructuring without the worry of harming a protected species.

Foam sprayed, bats deviated, repairs on the horizon, and, all in all, crisis averted.

For more information, please visit www.polyprollc.net.  •

Photos Courtesy of Elite Insulation & PolyPro LLC