How to Install Window Stool and Apron Trim Part 1

What You'll Need
120-grit sandpaper
Straight edge
4 hardwood boards, 2 by 2 by 36 inches
12 L-brackets with wood screws
3/4- by 12- by 12-inch hardwood plywood section
4 hardwood boards, 2 by 2 by 11 inches
Wood finish

A window stool is almost a necessity for houses that overlook a great outdoor view. It can provide you with a space for relaxation. It’s a nice spot to be in while reading a good book or for extra ornaments that you have lying around the house. It also adds a personal touch to an otherwise plain and simple window. You only need a few materials and a little carpentry know-how to build a window stool and an apron trim. Learn about the inexpensive and simple steps involved in transforming your window into a great space for recreation and creativity.

Step 1: Take Measurements 

The first thing you have to do is to take the measurement of the window where you want to install the window stool and apron trim. Find the length of the bottom edge of the window, the width of the window frame around it, the distance between the wall, and the edge of the window frame using a tape measure. Note these measurements when buying your materials.

Step 2: Make the Cuts

After noting the measurements and getting the materials according to those measurements, you should cut the wood accordingly to the custom fit of your window. Add 1/4 inch to the measurement that you got between the side window jambs and cut appropriately using a small circular saw. This is needed to give a reveal of about 1/8 of an inch on both sides. A reveal is an aesthetic technique used by experienced carpenters. This will add a professional air to the final outcome of your window stool.

Step 3: Install the Window Stool Cap

After you determine the final length of the window stool cap based on the measurements of the windows, you can start cutting a piece to the measured length. Be sure to make square cuts to minimize risks for errors. Also, recognize the return that you made. The return should be attached to the horn or the window stool cap in alignment with the straight bottom edge of the window frame. Always use good quality wood glue for these attachments.

Step 4: Notch out Both Ends

Measure the distance between the edge of the window sash and the edge of the window jam. You should also measure each side of the window frame at the bottom. These numbers will set how far deep you need the window stool cap notched properly. After noting the amount of material that you need to notch out both ends, measure the width of the side window trim and add 3/8 of an inch. Do this on both sides of the window stool cap. Check the measurement between the two marks and the one between the side window jambs. These measurements should be the same. If it's not, you should double check your numbers.