Buildings By the Numbers
- By Julie Sturgeon
- April 1st, 2005
You simply can’t erect a building without walls, a roof, and a few windows. But basic building blocks or no, you still can’t dissuade the folks with the calculators from squeezing as much life for their buck as possible.
Here’s how college facility administrators are handling the delicate balance these days.
Life cycle costing doesn’t fit neatly into columns when it comes to walls. That’s because while sane folks assume they’ll replace a shingle or window during a building’s life, they don’t plan for the walls to wear out. So here, number crunching evolves around determining the cost to operate the building during its existence, says Steve Loftis, marketing manager for North Carolina Foam Industries (NCFI) in Mount Airy, N.C.
In English, that means a story problem that reads: If a particular insulation method costs two to three times more than another, but reduces the utility bill by 20 to 25 percent every month, how quickly do you reach the break-even point? To further complicate the issue, manufacturers like NCFI can recite data for the more predictable, consistent residential market; commercial buildings vary widely on their energy consumptions.
But the gaps don’t rule out plugging spray polyurethane foam (SPF) into the equation, and anecdotally it’s holding its own in the outcome. After all, this material — which forms closed cells for a watertight seal, just as if you’ve stuffed a bag of ping-pong balls into the space — came on the scene in the late 1940s and was used to insulate refrigerator trucks and produce storage.We’ve opened walls that were more than 20 years old and the foam looked brand new, says Loftis.
The biggest drawback for university administrators remains the fact they must apply SPF at the construction or remodeling phase — you can’t spray it into a cavity after the fact. So the window of opportunity to tap into its money-saving properties is limited. On the other hand, because it’s not a standalone product that doubles for drywall, architects can spec it out on exteriors, cover it with stucco and wind up effectively insulating historic interior elements.
Colleges enjoy the same preservation benefit when they consider clear window films for existing buildings. But in the cold light of day, accountants don’t give much weight to that detail when sharpening their pencils. Luckily, window films can pass their criteria as well.
Advanced technology for windows means the average panes should last 20 years. The better designed ones last up to 40 years before the insulated glass fogs up, says Raj Goyal, director of Business Development for Graham Architectural Products of York, Pa.
So the missing quotient becomes how much to pay for the window and return on investment time. While films can’t magically answer the first part, products like V-Kool of Houston can offer studies showing the Department of Energy determined they offer a three percent fuel economy on cars. Because they block 99 percent of ultraviolet light, 94 percent of infrared rays and still allow 70 percent of the visible light pour in, those numbers convinced campuses like Stanford University, the University of Colorado and California Polytechnic State University to jump onboard. After all, they’re not only keeping some manmade heat in the building like a low-e pane, they’re also keeping the heat out.
No wonder Popular Science magazine recognized this science several years ago as one of the top 100 inventions of the past millenniums.
Another trap in window calculations: Some low-cost windows offered to universities at a 10 percent savings actually cost 50 to 60 percent more in the next few years because they aren’t designed for glazability, Goyal points out.If the glass breaks, it costs them 10 times as much to replace, he adds.
Enter window films again. V-Kool is testing a prototype five times thicker than current market offerings to see how well it stands up to bomb blasts. President Marty Watts knows this: when a golfer pounded a golf ball into his home window one weekend this winter, the glass broke into 50 pieces, but the film held it together instead of pelting them across the room.
Unlike insulation, the roofing industry has done extensive measurement on commercial roofing options, with preventative maintenance the lynchpin in the equation. And at the American Iron and Steel Institute’s (AISI) bottom line, metal offers the lowest dollar-per-square-yard per-year cost among today’s popular roofing systems.
Here, most building owners look for a minimum of 20 years from their roofs, says Joe Armbruster, general manager of Accel Roofing Products in Allentown, Pa. Unfortunately, that also depends on how well universities take care of that element, watching the sealants around curbs for ultraviolet light deterioration.
A proactive building owner realizes that if a roofing system is leaking, it typically doesn’t happen in one spot. You’re about to have continual degradation at that point, so the old adage ‘do you put a Band-Aid over it or do you cure it?’ applies, he notes. So when you take this effort into consideration, metal roofing costs the most upfront in both materials and labor but delivers the lowest per-year cost over that 20-plus year timeframe.