I’m contacted by publicists all the time with pitches about this or that product or designer. I rarely take the bait but I was intrigued by what Ottawa-based general contractor Paul Denys is doing on the restoration front, specifically his methods of reviving and restoring hundred-year-old windows to make them energy efficient and beautiful again. Denys is putting new technology at the service of old technology and saving the environment and his client’s money in the process.
Denys uses a pressurized steam box to soften and lift the paint on old window frames, then he uses a hepa vacuum to remove the paint without chemical stripping or sanding (which blasts harmful lead dust into the atmosphere). The glass can then be removed and replaced if necessary so the frame can be uniformly primed and painted, ready to be weather stripped and re-installed as good as new.
“To rip out all the old windows on an old house is going to cost the homeowner in the neighbourhood of $26,000,” says Denys. “The payback for that investment will take 60 to 80 years to recoup on the energy saving. I can improve a 100-year old window for as little as $250 by installing new weather stripping and new sash cords, waxing the runners to make them function properly and they’ll glide like they’re brand new. You’ll realize that saving in less than 10 years.”
A complete refurbishment with steam stripping and repainting costs about the same as a brand new window but Denys points out that the restored old window will last another 100 years, versus the 20-year warranty that comes on a new window. And while today’s homeowner won’t be here in 2113 to pat him or herself on the back for a job well done, the old windows have stayed out of a landfill site and the environment is being respected in the here and now.
“The greenest building is the one that’s already built,” says Denys. “Sometimes new is not necessarily better.”
“Windows are the single most expensive building component that go into a structure,” he observes. “The cost for windows in the average custom home is in the $20,0000 – $30,000 range. The problem with today’s windows is that the longest warranty we get on a thermal pane window is about 20 years. Hundred-year-old windows are a great example of a ‘keep it simple’ technology. It has a simple pulley with two vertical panes going up and down on a sash cord and that technology has lasted 100 years with few problems. I’ve seen 5-year-old double-hung windows with a sash that’s starting to sag because a spring has gone in it. And I’m pretty sure that if that window did last 100 years you’d never be able to find parts for it.”
As it happens, the parts required to rehab a heritage window are widely available. “There’s a spring balance from the Pullman company that’s been made since 1886,” says Denys. “It’s definitely not rocket science. We can replace all the parts with brand new ones. This is a robust technology that will easily last for another 100 years and I think you’d be hard-pressed to find a modern manufacturer of windows that’s going to give you a 100 year warranty.”
Denys works exclusively in the Ottawa/Hull area and you can contact him through his website. He’s also very positive about encouraging homeowners to tackle their drafty old windows themselves.
“Most of the energy efficiency of a window is realized through its weather stripping,” he stresses. “The Low-E Argon glass you can get today may add another 2 per cent energy efficiency, that’s it. If you can make an old window air tight you’re going to get 95 per cent of your energy savings right there.”
Photos courtesy of Gordon King Photography