Positive and negative hangar door impacts
It has always been my opinion that the hangar door system on any hangar for aviation is the engine and the yardstick by which that hangar performs. After all, you wouldn’t put a lawn mower engine in a race car and expect to win, right?
We must reevaluate based on more than that first cost of what you as a contractor, installer or architect are acquiring and integrating into a new build or retro fit/refurbished hangar on the grounds of:
• Safety (welding/engineering/electrical/stress)
• In-life maintenance costs (lowest part count possible)
• Overall building efficiency (does the door seal/carry insulation well?)
• LEED qualification
• Impact of door choice on building height/heating/cooling
• Hidden costs (e.g., the tracks and beams for sectional top-hung/bottom rolling).
• Will the door provide max useable width/ height for future proofing the hangar?
• Will the door actually last the whole life of the building?
• Is the door actually legal and insurable for the end user?
• Is the end user aware of the insurance risk (this is going to become an issue after several recent hangar door fatalities)?
There are many choices for customers and hangar designers along with some types best suited to certain size points, or for refurbished or new hangar projects. As much as I can wax lyrical with experience and evolution of the hydraulic door system for aviation, most customers are somewhat misinformed about the main types and size points, not to mention certain preconceptions about the limitations in terms of size some hangar door systems possess. Below is a very broad size/type optimization for your refurb or new build client/building door choices:
• Hydraulic Single Panel: 20 feet to 145 feet wide x 8 feet to 45 feet high (some manufacturers are size limited)
• Hydraulic Bi-Fold: 10 feet to 80 feet wide x 8 feet to 25 feet high (Hydroswing only)
• Cable/Strap Bi-Fold: 10 feet to 75 feet wide x 10 feet to 30 feet high (Note the wedge reduces clear opening)
• Bottom Rolling/Top Hung: 75 feet to 400 feet x 20 feet to 50 feet high (tracks and ground works required)
• Fabric: 60 feet to 300 feet wide x 18 feet to 45 feet high
The largest variable in hangar overall performance is door performance and hangar LEED efficiency. We should also continue to strive in this industry to grow a set of regulatory standards. I am appalled at the enormous concentration of standards on the hangar and almost no concentration on standards and certifications in the large hangar door sector. I would caution any general contractor to “buy-sell” any component of a hangar, especially a door, if they are not completely satisfied with the standards that the door is both engineered and fabricated to and evidenced by.
As a general contractor, architect, building supplier or installer, should a door fail or malfunction unsafely and with damage to life or property, be aware that you will be inside the chain of liability. I say this as we have seen in our international market in the last two years two fatalities under a bi-fold resulting in the banning of this type in the United Kingdom and Europe.
Questions and Considerations
The questions to ask your building supplier and door supplier irrespective of price/type/size are:
• Are your welders and shop certified too? (Request and file the proof.)
• Are your electrical components certified too?
• What fail-safe mechanisms are installed in the event of failure? (Request engineered proof and file.)
• Request technical paperwork to show engineering and analysis
(especially 45 feet and above), not just a cut sheet or sketch.
If you are also the installer and the provider of doors and cladding to a hangar project or refurb, you have a duty of care to yourself, your customer and your end user. Ensure complete visibility of a technically credible evaluation of what you procure, supply and install to make sure the hangar envelope is a maximum performer for the full lifespan of the building and beyond⎯safely and efficiently.
Designers, suppliers and innovators should strive to move the end product of the performance hangar system out of the dark ages and into a new level of build, use and own efficiency at all levels of the supply chain. It is very important to provide in-life value total cost of ownership, rather than simple cheap on the front end.
Marshal Parker is president of Hydroswing Hydraulic Doors & Walls, Carlsbad Calif. To learn more, call (858) 461-4519 or visit www.hydroswing.com.