///Making Historic Windows More Efficient

Making Historic Windows More Efficient

Shaker Life’s green building expert talks old windows.

By Michael Peters

Arched window

Windows are an important design feature in many Shaker Heights homes, from French Classical to Midcentury Modern. Unfortunately they are also often inefficient, drafty, and may not operate very well.

There are many ways to address these issues. You may find a combination of solutions best fits your needs. This may range from seasonal films to interior or exterior storms, or complete replacement.

Our home, built in 1931 in the Tudor Revival style, had three different types of windows when we bought it: the original steel frame windows (many with leaded glass), replacement windows that were installed in the 1990s, and glass block windows in parts of the basement. Most of the windows are 19 inches wide and 40 or more inches tall. All of the original steel frame windows are single pane, while the 1990s replacements were designed to have an interior storm window. The replacements are single “lite” windows, meaning there is one pane of glass — a very different look than the originals with the divided panes and lead details.

While many homeowners might opt to install replacements, modern windows have large frames made of wood, vinyl, uPVC, or aluminum-cladding. Installing these in our narrow windows would have reduced our glass area by two inches or more – making already narrow windows appear oddly narrow. These replacements, as is required in Shaker Heights, would  need approval by the Architectural Board of Review (see shakeronline.com for more info).

So our solution was a combination of options. We restored the original steel frame windows (there are several very good leaded glass artisans locally) and fitted them with interior storm windows and cellular blinds, which had the added benefit of making the house quieter. They now perform as well as many replacement windows and will for decades to come.

For the 1990s replacements, we had our leaded glass contractor create new inserts that replicated the diamond pattern of the originals, which unified the look of the house. Finally, this summer we will replace the basement glass block windows with new uPVC triple pane windows.

We decided to use this particular window in the basement for a few reasons. We wanted low maintenance and the windows are in window wells, so uPVC is durable and much more stable than vinyl frames. We also chose triple pane windows because the u-value, which is similar to the r-value of insulation, makes them very energy efficient for a relatively small price premium (the u-value is a good way to compare windows). Finally, we chose windows that are Passive House certified because they are airtight and part of our air-sealing strategy (see phius.org for a list of certified windows).

Equally important to choosing the right replacement windows is the installation. While this is a technical detail it is important: Make sure your installer is using a method of installation approved by the American Architectural Manufacturers Association. This ensures that there is proper flashing around them to keep water and air out, greatly improving window performance. If you have an older home, also make sure your contractor has passed the EPA’s Lead-Safe certification program to minimize your family’s exposure to lead paint dust.

There are numerous other strategies that are far less costly than restoring or replacing your windows. Start by simply using a window film, available at your local hardware store, in the winter months to see if this helps. Replace typical window shades with cellular blinds and heavy curtains. And make sure the seal around your windows, both inside and out, is not cracking or missing – caulk is the best value for your home improvement dollar.

Window replacement is costly and should be undertaken after you have exhausted other options. There are good resources to help you decide on the best solution, including the Cleveland Restoration Society (which is free to Shaker residents), the Home Repair Resource Center in Cleveland Heights (Shaker residents receive a discount on classes), and architects and sustainability consultants. Most of all, invest in quality windows.

Michael Peters, LEED AP, is a green building expert who lives and works in Shaker Heights. Follow him on Twitter at @CoventryLand.

Originally published in Shaker Life, Summer 2016