|
Fri, Nov 7 2008  Posted by: Rick Arnold
One of the most cost-effective energy upgrades to an existing house is replacing the old windows. Not only do replacements provide more insulation, but their installation also provides the opportunity to air-seal around each unit. Especially here in New England, it’s often possible to see payback in as little as five years.
On this historic-building project, we have a mixture of double-hung windows. Some seem to be original (1750s) while others have been altered, repaired, and replaced over the years. Judging by the hardware and the glass, I would say that except for a stray pane of glass here and there, none has been replaced since the 1800s.
Unfortunately, the one thing they have in common is that they are all in bad shape. While the majority of the frames are not too bad and can be worked on, the sash in most are not worth saving. Much of the wood is rotted, and many are held together with modern L-brackets. The ones that seem to be in better shape have been sealed shut with layers of interior paint.
 We asked the historic commission about replacing the windows. We brought in a sample of a modern, energy-efficient window that replicates the historic look in the dimensions of the wood frame, sill, and sash, and also the look of the glazing, in that it is true divided lite.
No way, no how, forget about it!
I can understand some of the resistance to the change. The existing glass panes are beautiful with their imperfections (waviness, distortion, and small bubbles), but it would have been nice to have the replacement option for some of the less visible units around back.
In the meantime, I got a quote from a local historic-building restoration company to repair the existing sash. The estimate range was from $500 to $1600 per window (per sash, actually) to get them back to properly functioning, structurally secure units. But there is no guarantee of success because many of the units are only 7/8 in. thick and very flimsy.
So if we take an average of $1000 per window, that comes to about $45,000. To that I say: No way, no how, forget about it!
So what now? I know we can install storm windows on the outside (which many already have) and also on the inside to improve energy performance, but there is still the issue of being able to operate the sashes during nice weather without them falling apart.
I would appreciate any suggestions.
|
