Innovative Awning System On A Retaining Wall

What do you do when you decide to put a pool where you originally planned to install a solar power system and the roof won’t work?

You get the determined folks at TRA Snow and Sun to help you think outside the box and create something we think is an innovative concept!  That’s what contractors of the Bourne, Massachusetts home project did when they encountered this issue on the project being constructed in a beautiful wooded area with a steep hillside at the back of the property.

Here’s what transpired.

Plymouth Solar Energy of Plymouth, Massachusetts was assigned the task of determining where to place the solar energy system during the construction of a large home.  After making the site visit, Greg Aborn of Plymouth, determined that the terrain was unsuitable for a ground mount system.  The soil was too sandy, unstable and steep.  When the owners disclosed that they had now decided to build a retaining wall and put a pool, Greg began research into alternative solutions.  This is how he discovered TRA Snow and Sun’s Awning Solution.

Greg says, “I am very strict with the quality of materials and products that I will allow for any of our installations, so I began digging deep into the awning- racking materials, engineering, installation methods/requirements, grounding, mid/end clamps etc… I was very pleased with TRA’s product in every way.”

Gary Heslington, of TRA Snow and Sun, was involved in the engineering and designing which began as a new concept – an awning system attached to the retaining wall, which was still in the design stage when he came on board. TRA worked hard on several different designs, trying to find one that would work well for the solar installer and homeowner.  He says, “When the concrete retaining wall idea was included where the awning system was eventually attached, we had to do three complete revisions, and then it took several months for the property owners to approve.  But we stayed in touch and were very happy when we got the go-ahead from Plymouth.”

TRA Snow and Sun has a reputation for creating engineered systems for solar mounting and roof snow retention systems and are very adept at thinking outside the box.  They used all of their experience (25+ years) and resources on this project.  The engineering and time spent was free.

Greg Aborn explained some of the difficult aspects of completing this project, “Mounting a highly visible system in a tough environment for exposure to the elements meant I needed to place significant emphasis on system durability and longevity.  I would bet my last dollar the wall will fail before our system does!”

To install this solar panel system, they fabricated custom scaffolding which allowed the installers to stage the wall in sections while not disturbing the soil retention (special grass to hold the soil together) that the homeowners were required to plant in compliance with tight property set-backs.  Erosion concerns with the abutting neighbor and steep property topography leading downhill were also factors in the installation.

TRA’s mounting system, combined with creative problem solving, eventually overcame what seemed like insurmountable obstacles across an extremely complicated range of municipal regulations and restrictions.  The finished product exceeded the homeowners expectations and created a solar power system that creates 12.3 KW of energy while conforming to the requirements of both local authorities and the homeowner.

In the end, Greg Aborn has high praise for TRA Snow and Sun’s products and service, stating, “I hope this puts as big of a smile on your face as it does mine!! I want my salesmen to sell a whole lot more of these!!”

Plymouth Solar Energy – http://www.plymouthsolarenergy.com/, (508) 746- 5430, 18 Main Street Extension, Suite 204, Plymouth, MA 02360

 

 

Case Study – Glendale Library, SLC, Ballasted Solar System Required Creative Solution

The Problem

The new Glendale Library in Salt Lake City, completed in Spring 2015, offers 20,000 square feet of media and meeting space for a diverse populace in an older section of the city.  Designed with an EPDM membrane roof, and achieving LEED Certified Gold rating, Intermountain Wind & Solar was contracted to install solar panels.  However, with a 115 miles per hour wind speed rating, and a maximum allowable five pounds per square foot dead load on this building, they needed an unusually light ballasted solar mounting layout.  But the Class C exposure category of the building added additional complications.  The problem was apparent:  How do you stay under the 5 psf dead load requirement but provide enough ballast for the class C exposure?

solar racking for flat roof

The Solution

Intermountain Wind & Solar contacted TRA Snow and Sun, Inc., of American Fork, Utah, designers and manufacturers of solar mounting and racking systems.  TRA frequently engineers ballasted mounting systems, with arrays that are completely interconnected, one right after the other, commonly spaced out six feet apart with 100-200 lbs of ballast weight per tray.  However, this typical layout wasn’t going to work in the case of the Glendale Library.  The engineers at TRA and the folks at IW&S had to be creative to keep the weight of the system under 5 psf but provide enough weight for the wind speed and class C exposure.

The integrators originally considered spreading out the panels to lessen the impact/weight on each rafter/truss, so TRA Snow and Sun suggested a layout with all panels close together and the ballast trays linked as well, creating an interconnected solar mounting system.  However, since all of the ballast was tied together in the system, the weight per square foot was uniform over a small area and overloaded the localized rafters/trusses.

ballasted solar mounting

The solution to this loading issue was to separate the continuous, closely laid out array, and create smaller arrays. These smaller arrays were still interconnected in the north/south direction but with a  gap  created in the east/west direction.  Each smaller array only had one tray per 3 panels, therefore reducing the amount of ballast on the rafters/trusses drastically.  The new design allowed the load per tray to satisfy the required ballast for a 115 mph wind load and a class C Exposure.

According to Jake Owsley, TRA sales team member who worked on this design, “The result of our efforts created a uniform, functional system providing adequate maintenance space, while also satisfying the necessary requirements for the Glendale Library.”

ballast solar mounting system

Case Study: Solar Tile Mount Provides Adequate Air Flow between Solar Panels and Tile Roof