We’re all aware to some degree the energy savings that can be realized with the right windows in your house. And, many of us have faced the dilemma of moving forward with these efficiency upgrades while limiting the aesthetic architectural damage that might come to a coveted home as a result.
Many of the finest homes in the country lay in old well established neighborhoods and were built some 80+ years ago. And their character, their charm, is often the result of beautiful leaded windows or small divided light windows. But, while maintaining them in good condition can help, generally speaking, from every aspect of modern window science they fail – bad seals, single pane, and no coatings.
I believe that historic homes require some energy math to find saving improvements where they can best be implemented. Extra attic insulation, high efficiency furnaces or boilers, tight seals on all of the windows and doors and basement insulation are effective measures. About 10% of your heat is released through uninsulated windows but the biggest bang can first be had from these other improvements. As for the windows, it’s likely they’re not all of the intricate design variety and replacing the ones that aren’t can help. Finally, storm windows can be installed on the interior or exterior of the home during the coldest months for these instances where history must take precedence.
Window Replacement Options for an Older Home
The 1940’s marked a time where windows began to open up, so to speak. Divided lights either with mullions or lead were used less as people began to desire clear views of the exterior. So – here we are, undeterred, and able to explore all possible window replacement options.
Here are some of the choices available today:
- Frame material: Wood, Vinyl, Aluminum, Fiberglass, Vinyl Clad Wood, Aluminum Clad Wood.
- Insert vs. Full Frame Replacement
- Fixed, Double-Hung, Casement, Awning, Sliding, Screened
- Glass: Low-E, Argon gas filled, ¼” or ½”, or triple paned
Replacement windows can add a great degree of comfort to your home. Lower conduction means warmer windows, lower convection means less drafts, and lower radiant heat transfer gives us benefit from the sun during all seasons.
A few things to note:
- Aluminum should be avoided as it transfers heat. It can be ordered with the proper thermal breaks to minimize this where the architecture calls for it.
- Wood requires the most maintenance, but looks best, and since painted, is the only choice that allows you to change color.
- Vinyl is very durable and, since the color goes all the way through the vinyl, some soft scrub can bring them back to near new condition.
- Low-E, argon gas windows cost on average about 10% more than just clear glass. However they are the most energy efficient window available and a rough rule of thumb is a payback of about 4 years.
But what if you don’t want to replace the windows?
- Drapes which are closed against the wall at the window top, sides and bottom and are lined with a light colored material trap the hot dead air of summer and the cold dead air of winter. The key is restricting airflow and this should also include overlapping center.
- Horizontal blinds are best able to reflect unwanted sunlight and it’s heat generation, and blinds made of vinyl or wood are least conductive and can provide some incremental heat savings when closed.
- Outside shading can be particularly effective in warm climates where your primary mission is cooling. Similar to this, the Low-E coating is placed on the inside glass where heating is primary and on the outside glass in more cooling-centric environments.
Good windows, window coverings, and good light management can save you energy, money and give you comfort – of the cozy type. With the efficiencies of today’s windows, larger windows that provide more natural light can help save on lighting and should be considered as a part of your window replacement plan.
Michael Samsel is an entrepreneur and writer on the subjects of home design and green home practices. A co-founder of StylishHome.com, their “good design” mission emphasizes individual design personality, the eclectic and hand-made, and a commitment to green home pursuits.
Not quite ready to replace those old windows? You can still make them more energy efficient with window coverings, including shades and window film.
Image credit: Orin Zebest at Flickr under a Creative Commons license
If you look for the old study by the Rocky Mountain Institute, “Cool Citizens Guide”, you will find that window replacement delivers the worst bang for the buck of just about anything you can do.
If you look at the website of the National Trust for Historic Preservation, you will find twenty different studies showing between a 40 year and 400 year return on the investment in replacement windows. You will also find demonstrations of how to fix your windows so that they have a U value within a few percent of new windows.
replacing windows can dramatically change the look of a house and hurt its value. any prewar house is going to have windows made of first growth wood that will last hundreds of years. But window replacement is hugely profitable for the contractors and hard to resist, even though a couple of tubes of caulk will save as much energy and carbon.
There are clever new magnetic and snap-on storm windows that can stop the draft and reduce energy consumption for a tenth the cost of a new window.
I should note that I volunteer as the President of the Architectural Conservancy of Ontario, and spend much of my time arguing about replacement windows.
Lloyd — Thanks for chiming in… very useful (and I say this as the owner of an old home with original windows).
Thanks for the comment. I too have an older home and the diamond patterned leaded glass will never get touched. However, we did replace the windows on a mid-century styled home we previously owned… lots of big single pane glass, and the difference in comfort and $$ were notable. But never really did the math.
Your point is well taken and I hope I left people with the idea that windows require a measured response when it comes to the question of replacement.
I will check out the websites you reference.
And – when done, hoping people give good consideration to aesthetics.
There is a ingenious new product that preserves your old style windows and give you the advantage of double pane windows. Indow Windows custom fits an acrylic glazing with a patent pending spring bulb edge that seals a airspace between the original window and the Indow Window.
I READ YOUR ARTICLE ON REPLACEMENT WINDOWS AND AGREE THAT THERE ARE MANY ADVANTAGES IN THE DOUBLE HUNG OLD WOOD WINDOW WITH STORM WINDOWS AND APPROPRIATE WINDOW TREATMENTS TO INSULATE. THE PROBLEM I HAVE IS THAT MY HOME IS FORTY NINE YEARS OLD AND THE THE GAS BETWEEN THE PANES OF GLASS HAS FOGGED THE WINDOWS AND MAKES IT DIFFICULT TO SEE OUT OF THEM. IT SEEMS THAT CONTRACTORS DO NOT WANT TO REPLACE THE GLASS BUT THEY WANT TO REPLACE THE ENTIRE WINDOW. DO YOU HAVE ANY SUGGESTIONS.
I have found Renewal by Andersen windows to be a good option for historic homes, particularly in the New England area where I am at. They can be pricey but because they are custom measured they seem to be the most energy efficient for older homes that may have warped window frames.
I’ve put them on my home, James. You’re right, they are expensive, but really good replacement windows…