Restore or replace vintage windows?
I’m considering three options to improve the performance of the 10 double-hung windows that remain in my 100-year-old house in Zone 4C: replacement with inserts; retrofitted weatherstripping; storm windows.
My understanding is that replacement windows cannot be rationalized on the basis of reduced heating bills. Rather, the argument for replacement windows turns on comfort — the reduction of air movement and of radiation makes it more pleasant to be near them. Questions: How much more comfortable is a replacement window than a well weatherstripped vintage window? How much help is a storm window? How does one measure and predict “comfort?”
A couple of specific questions about window restoration:
In a FHB article, the author claims that, with the use of weatherstripping from Conservation Technologies, a restored old double-hung can be rendered “as weathertight as anything being made today.” Has anyone installed these products? Are they as effective as the author claims?
The weight pocket of a double-hung must allow a lot of air to move. What if I removed the weights, filled the pocket with foam, and installed a Pullman spring balance to operate the sash? Has anyone used this method?
http://www.finehomebuilding.com/how-to/articles/renovating-historical-double-hung-windows.aspx
http://www.conservationtechnology.com/building_weatherseals.html
http://www.pullmanbalances.com/
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Replies
Ray,
It sounds like you've done your homework. If you are willing to repair your existing windows, that's the way to go. You can do the work yourself, or hire an experienced contractor to do the work.
Once you have made adjustments to improve functioning, installed new weatherstripping, perhaps replaced the sash locks, and in some cases filled the sash-weight pockets, the final step is to install low-e storm windows.
Ray,
Here are links to two Green Building Advisor articles that may be useful:
Replace That Window?
Should Historic Preservation Trump Energy Performance?
If you can find someone who knows how to install metal interlocking weatherstrip, that's even better - look at Accurate Metal's offerings.
There are other ways to tighten up the weight pockets. I am loathe to mess with something that's worked well for 100 years and probably has another 100 in it. Nothing you replace it with will last half as long.
I know this will make Martin grit his teeth, but:
In my opinion the only way to get an antique window to be at least partly airtight involves removing it from the building, since it was never sealed or intended to be sealed originally. In doing so you will doubtless find that some pieces are beyond their practical life, IOW rotten. and need extensive rebuilding.
It is also my opinion that whatever strategy you use for sealing the sashes to the frame is to some extent temporary. Wood moves grows shrinks and shifts and those sashes were never intended to be airtight and will continue to leak air to some extent, and this will grow over time, especially if they are used regularly. There are good companies that make these weatherstrip products but they are very dependent on the quality of install and if you are paying for the labor it is going to add up.
Once this is done, you have the honor of maintaining via paint and putty on a regular and ongoing basis. I have watched panes fall out of their sashes behind storm windows.
While storm windows are less expensive than new windows they are still real money, a quick search finds a decent looking triple track with screen for 150 bucks, while The Despot has them down to 60. None of these are air tight or Low E.
The Despot will also sell you an Andersen 400 series for less than 400 bucks. They will also sell you a vinyl window for less than 200 bucks[all the prices are for around a 3 foot by 4 1/2 foot window]
It would surprise me if the actual bill for properly refitting antique windows and adding a good quality storm window was actually significantly lower than the cost of installing a decent quality replacement window.
If you are doing the labor yourself, then you will be cheaper since you are free, but people herabouts who are worth hiring run 25-50 an hour and that adds up in a hurry. If you love the look of antique windows[which actually I happen to] or are legally required to save them, then this sounds sensible.
Take none of this to mean that you should buy a house full of windows from the guy with bad breath a lime green polyester sport jacket and the magnetic sign on his truck,
Restoring old windows is a labor of love, or the product of intense hatred of vinyl windows, but I think both long and short term it is not a big financial gain
If you go with new windows, Marvin Integrity offers custom sizes and SDL grills (glued to the inside and outside of an insulated pane), and have a "look" that closely resembles old windows. And they are fiberglass so will last a long, long time.
Pretty much any manufacturer can do SDL's and custom sizes. I guess I'd think about: how long are replacement windows going to last compared to restoring the old ones, the character of the house and how replacement windows will affect that, and other places in the house the money might be better spent in terms of thermal efficiency and comfort.