Introduction

Here's a way to add a little extra space to your windows.

Some of my fondest childhood memories involve window stools installed on the sills of old-fashioned double-hung windows in a rustic cottage facing a lake.

Each summer, I’d ride my bike down to that lake to visit Alice and Mike, a lovely elderly couple who were like adopted grandparents to me. One of my favorite parts of these visits was digging into the fresh apple, raspberry or blueberry pies Alice always seemed to be baking. Somehow, every time I arrived, she’d have one cooling on her window sill.

It wasn’t until I was much older that I realized each sill had a sort of built-in shelf called a window stool, giving her space to set cooling pies and other items.

The instructions below show how to make and install window stools over existing window trim. My window trim includes a decorative rectangular strip on the inside and outside edges of the casing.

Retrofitting a window stool over this sort of large, old-fashioned trim can be tricky, requiring a lengthy list of woodworking power tools and some precise cuts. But the results are well worth it. If your trim is more modern and simpler, you may not need all the steps and notches you’re about to see.

Either way, this step-by-step guide will get you to the finish line.

Keep in mind the stool shown in Figure A and the photos below are for larger-scale casing that’s 3/4-in. thick and four inches wide. For modern, slimmer casing that’s about 7/16-in. thick and 2-1/4 in. wide, the stool should project from the wall only about 2-1/2-inches

Want to revive this useful detail of window construction at your place? Keep reading and learn how to make new window stools so you can have somewhere to set cooling pies or anything else you like.