Below is text from an article I wrote in November of 2012. It was published in the Central Brittany Journal.
Can replacement windows pay for themselves in energy savings?
Yes – in about 250 years!
I bought my first old house in a small town in Canada famous for its historical homes. One of my greatest challenges in restoring that late 19th century house was the many windows. The previous owner had installed aluminium storm windows which trapped moisture causing much of the original woodwork to rot away. Replacement windows would never have suited that house. I took on this challenge and returned the windows to their former glory. Along the way, I discovered the best products available and honed my techniques while getting progressively faster with each restoration.
Often, one hears that replacement windows can save significant amounts of energy thus enabling them to recoup their cost quite quickly. However, many recent studies have shown that the difference in annual energy savings between a refurbished original wood window and a factory-made replacement unit amounts to only a few Euros. In fact, some calculations have indicated that the payback period on installation of new windows could be as high as 250 years!
Original windows are often constructed of dense old-growth lumber which is more stable & resistant to rot than the lower cost finger-jointed wood often used to construct windows today. Depending on the climate, some have been known to rot out or fail in as little as five years. Lower cost vinyl units can deteriorate quickly as well. Old windows were built to be repaired.
Restoring your windows is an attractive option for several reasons. Windows are one of the most important aesthetic features of any building. They can either enhance the façade or seem jarringly modern. In recent years, many home buyers have been known to search specifically for homes that retain their original elements. A refurbished window is always historically accurate for the house it is set in. It can be painted in the perfect colour and does not require any permits or cause construction delays. Other benefits include the relative ease of work. There is no need to disturb the structure of the building with drills and hammers and the entire process creates little dust and debris. It is easy to restore a single window or many at a time, allowing one to choose the scale and cost of the job.
Well maintained windows add character and value, show your appreciation of quality workmanship and make your home more energy efficient. If your windows have served your home well for many years (or centuries), consider the benefits of restoring them so they may continue doing what they were made to do.