Historic Window Restoration by Westbrook in Seattle
When it comes to evaluating historic windows, the first thing I like to do is assess the amount of decay on each window system, and determine how much of the window should be removed for repair. Can we repair the window just by removing the sash, or do we need to remove the entire system including the jambs? Removing the whole window will require the craftsperson to extract the more expensive interior and exterior trim, so it’s best to do that only when necessary. Be sure to preserve all window parts and pieces; this is critical for understanding the exact sizing of each window, matching new components, and determining if there have been modifications made over the years. In many cases, historic window modifications are performed incorrectly, which require an eventual fix. Setting up dust controls in the living space is also critical as it keeps dust down while being compliant with lead contamination regulations.
Removing historic windows is a surgical process requiring precision on-site, in transfer, and in the shop. You’ll need a disciplined level of organization and a gentle touch! With that, it’s important to remember that agitation should be kept to a minimum, because plaster and mouldings are fragile, as are many of the window components. It’s best to gain knowledge about how installation was performed in the first place. From there, you can use your knowledge (along with a myriad of pry bars and specialty saws) to keep damage at a minimum. Paying careful attention to the original assembly during extraction will give you a better knowledge of how the windows were installed in the first place, and understanding how the 1900s-era craftsmen installed the windows will help you in your extraction and re-assembly after repair. Once extracted, I like to use a numbering system assigned to each piece. I also use a HEPA vacuum to clean as we work, because, again, this is more like surgery than demolition.
How long will these historic double-hung windows last? With proper restoration, we’ll have to wait another 100 years to find out.