Remember when you were a kid and you drew pictures of houses? Each house had a triangular roof, square windows and a rectangular door—until some predictable spurt of brain development prompted you to add shutters to the windows and your parents declared you a savant.
I’m guessing you probably never thought much more about shutters after that. I know I didn’t. Until recently. These days, I think about shutters a lot.
I think about the overall dimensions of the shutters and the thickness of their horizontal rails and vertical stiles. I think about their precise mortise-and-tenon construction, which leads me to think about attaching copper caps to their tops—so rain doesn’t seep into that precise mortise-and-tenon construction—so the shutters will last longer. I think about how many louvers are in each section of a shutter. And how much space is between each pair of louvers. I think about how much space lies between the bottom of the shutter and the Bottom of the Center Rail. In custom shutter argot, this span is sometimes called the BCR.
There are a lot of measurements to consider when designing shutters, and the numbers can seem pretty arbitrary, until you think about what shutters were for in the first place: protecting a house from intrusion by humans, light and weather.
That’s why shutters are traditionally affixed to the house with hinges: so you can throw up the sash and reach outside to pull the shutters closed. With that functionality in mind, shutter specs start to make sense:
Generally speaking, dimensions of a shutter should be half the width of the window-by-the full height of the window, so the pair of closed shutters can protect the glass.
The BCR should be situated so the center rail aligns with window sash rails. Think about it this way: If you are inside the house and the shutters are closed over a double-hung window, the shutters’ center rails should be directly behind the horizontal window rails.
Since one of shutters’ main jobs is to keep weather out of the house, louvers should slope down away from the house when the shutters are closed.
These days, windows are better sealed and insulated than in the past, so shutters’ work is increasingly decorative. Kind of like keystones over non-arched doors and windows. Or belt loops on jeggings. As shutters have lost their weather-protection raison d’être, they’ve also lost their design logic. Look around and you’ll see shutters that are too tall to close in the window’s recessed frame, or too small to cover the width of windows. You’ll see single-wide shutters flanking double-wide windows. You’ll see louvers that would drain water right back into the window if they were closed. You’ll see shutters that lack hinges, so they couldn’t close in the first place.
Armed with what you now know, take a look around. The shutters you see might amuse you. Or they might drive you crazy. Either way, you’ll never see shutters in the same light again.