Historic windows, most notably double-hung windows were brilliantly designed. They have several benefits that are simply not found in a replacement window today that make them an important architectural feature to save. And I believe that once you understand how they work and their ultimate value to your home you’ll want to save them if at all possible.
1. They Are Efficient
Contrary to popular belief old windows can be an efficient part of your home’s envelope. The problem is that many old windows have either lost their weather stripping or never had it to begin with. Adding this important element can really increase your old window’s efficiency and make them competitive with a replacement window.
And if efficiency truly is important to you, the addition of a historic storm window can bring an original window’s performance up to 94% of the efficiency of a replacement double-paned, low-e window at a fraction of the cost.
2. They Add Value
A large part of the value of any old or historic home is the presence of original details like windows. Most buyers of these types of homes appreciate and expect to find these original details and will pay a premium for homes without replacements. And to find to house with restored original windows along with other original elements is a rare gem that commands a much higher selling price.
3. They Are Incredibly Resilient
Original wood windows on homes built before WWII are more than likely made from “old-growth” lumber. This wood came from the huge virgin forests that once covered North America. As this supply of wood was depleted we slowly turned to tree farms to keep up with our growing demand. But “old-growth” wood is a far superior product than any wood you can buy today. Due to the slower growth patterns “old-growth” wood is stronger, more stable (less prone to cup and warp), and more resistant to insects and rot. Why you would ever plan on replacing this far superior wood with a vinyl or aluminum clad replacement window is beyond me.
4. They Are Simple & Easy to Repair
The more complicated something is the more likely it is to break. And windows are no exception to this rule. Historic windows operate on a simple rope and pulley counterweight system. Sash cords are fit into holes mortised into the side of the sash and then run over a pulley and tied to a iron weight which is hidden in a pocket inside the window jamb. These weights provide perfect balance and a smooth almost weightless operation to the window.
In addition, there are no seals to wear out or gaskets to dry up on an old window. It is a simple solid wood frame with a piece of glass held in place by little metal points called glazing points and then glazed with a natural putty that provides a flexible seal for decades. When the putty dries up after 40 years or so you scrape out the old and apply new putty. If the wood frame suffered rot or damage it is easily repaired as well.
Historic windows are a DIYer’s dream since there are no factory parts of complicated replacement procedures. They are designed to be simple and effective.
So, that’s it! Hopefully, I’ve given you a few things to think about before you tear out your old windows and buy off-the-shelf replacements. The payback for restoring and maintaining your original windows is almost immediate compared with the decades long wait (if ever!) for a return of your investment on replacement windows. With an old house it’s always best to move slowly and take your time before making any permanent changes. And your windows are just the start.