YES, Old Wood Windows Can Be Energy Efficient!

One of the most common things we hear is, “old wood windows are not energy efficient.” This idea becomes the rationale behind why many old wood windows end up in the landfill. Unfortunately, many people are misinformed and fall for these claims that wood windows are not energy efficient.

The truth is old wood windows can be made just as energy efficient as new, double-glazed windows. Like any building component, they need the necessary care and upkeep to maintain both operation and energy efficiency.

Original wood windows can compete effectively against newer replacements when these needs are met:

Properly Maintained

Just like we take our car in to have the oil changed to keep it going, wood windows need regular maintenance to keep them operating. Since wood is a natural substance, it is vulnerable to deterioration, moisture, and pest infestation.  

To stand up to the outdoor elements, the exterior wood needs to be kept painted. If you notice the paint or finish is cracking or peeling off, it means the wood is exposed to the weather. Painting wood seals and protects it from the elements, which is why maintaining the paint or finish coat on wood window frames is so crucial.

Another important, and often overlooked, part of window maintenance is regular cleaning. Letting dirt and grime build up on window surfaces deteriorates the finishes and impedes operation. Clean windows regularly with mild household detergent, or a mixture of vinegar and water. Heavier buildup or mold and mildew can be dealt with using a soft-bristled brush.

stained window on brick wall

Repaired as Necessary

Like anything with moving parts, window parts wear out over time. Typically, paint buildup, broken sash cords, and general wear and tear over time causes them to stop working correctly. Wood windows need repairs occasionally to fix broken parts. After years of painting, excess paint needs to be removed, and they need to be repainted properly. Trim stops and sash locks often need to be adjusted so they work as intended. A repaired wood window sash fits well, moves easily, and keeps out drafts and weather.

Forcing windows open or closed is a sure sign of a problem. Make repairs right away so that continuous jamming and slamming of the window doesn’t further damage it.

Broken panes and cracked or missing glazing is another common repair. When these areas fail, naturally the window becomes far less energy efficient.

Fitted with Storm Windows

An original old wood window combined with a storm window is about 15% more energy efficient than that new replacement window.

Installing storm windows offer tremendous improvements in energy efficiency. They are also much easier and less intrusive to install than replacing a window. Storm windows not only improve the overall energy efficiency of windows, but they help protect the exterior window surfaces, saving on maintenance. Adding quality storm windows will allow you to improve energy efficiency and save your historic wood windows at the same time!

Quality Weather Stripping Installed

Installing quality weather stripping is essential in improving the energy efficiency of wood windows. According to the Department of Energy, you can save an average of 7.5% on your fuel bills by fixing air leaks around windows (and doors) with weatherstripping. On average, weatherstripping pays for itself in 1-3 years.

There are a lot of various weather-stripping materials on the market. The cheaper, stick on versions really just don’t cut it. While it’s more expensive and more involved to install, we only use metal interlocking weatherstrip. Besides what you will save on your energy bill, metal will last for decades. It provides the best air seal. Another nice bonus of metal interlocking is that it will also improve the operation of your sashes. They will glide smoothly against one another, and close easily into place.

meticulous work

A Note About Lead-Based Paint

Old wood windows may have lead-based paint (LBP). LBP is definitely a hazard and can be very dangerous when disturbed. A window restoration professional can take care of removing LBP from your windows and repainting them so they are good as new. What you need to know about LBP.

It is Definitely NOT Better to Replace than Restore

When it comes to energy efficiency, both for the building owner’s budgetary concerns and comfort, as well as considering sustainability of the planet, the “greenest” windows are the historic ones already in place. When they are properly sealed and maintained, an original wood window beats replacements for efficiency, will last much longer than a modern replacement, and preserves the historic integrity of the building.

Window Repairs & Restoration is Our Specialty!

At Kronenberger & Sons, we have a shop dedicated specifically to the repair and restoration of historic wood windows. Our window shop handles all aspects of window repairs including woodwork, glass and glazing, and paint removal and repainting. We are lead abatement certified and follow strict protocols for both the removal of windows on site, to their paint removal process in the shop. Learn more.


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