Historic Wood Windows: Repair or Replace?

Energy savings studies have demonstrated that a historic wood window, properly maintained, weather-stripped and with a storm window, can be just as energy efficient as a new window. Windows contribute only 10-12% of overall infiltration to the building envelope. Much more infiltration occurs at roof eaves, foundations and even through wall receptacles, dryer and plumbing vents, and fireplaces. According to studies, it can take 60 or more years to recoup enough money in energy savings to pay back the cost of installing replacement windows, but by this time, the new windows have already failed and been replaced again several times over. More cost effective energy savings ideas include installing awnings, operable shutters or insulating window treatments to reduce heat gain, plus adding wall and attic insulation, caulking/sealing around wall and roof penetrations, and installing solar powered attic fans.

Each year, Americans demolish 200,000 buildings, creating 124 million tons of debris. Every window that goes into the dump adds to this problem. Replacing historic windows discards the embodied energy that was used to create the original windows and requires the consumption of more energy to produce the new windows. In addition, replacement windows that contain vinyl or PVC are toxic to produce, create toxic by-products and are not recyclable.

The original wood windows on a historic home are the architecturally correct style and proper proportions for your historic home. Replacing unusual shapes and historic sash patterns often requires expensive custom replacement windows or replacement with a lesser design. Standard style replacement windows often have different frame and muntin profiles that are oddly proportioned on your historic home as well. In addition, metal and vinyl windows do not hold paint well, and are generally stocked in glaring white which does not look aesthetically pleasing on many historic home styles.

Repairing rather than replacing historic wood windows retains the original historic fabric of your home. Once they are removed, they can never be truly replaced in kind.

When the original wood windows are painted shut, have broken sash cords, broken glass or a portion of the sash or frame is rotted or damaged, the windows are almost always repairable by a carpenter for a fraction of the cost of replacement windows. In addition, repairing historic wood windows does not require modifications to the existing opening framing or replacement of historic trim, which can add unexpected costs to your window replacement job.

Your wood windows already have a 75+ year track record of service and are infinitely repairable with standard carpentry tools. Most modern replacement windows have an expected life span of 10-20 years before the springs fail, seals break and the glass clouds. These replacement windows do not have replaceable parts, so when this occurs, the entire factory-made unit has to be replaced, starting a continuous cycle of required replacement.