How to Build a Classic Window Box

Window boxes brighten up the façade of any home. Follow these instructions to build some for the front of your house.

Highlights:

Step 1: Determine the Length
Step 2: Cut the Pieces
Step 3: Build the Box
Step 4: Install the Window Box
Step 5: Plant the Plants

Step 1: Determine the Length

Measure the window opening. A window box should be the same width or slightly larger than the window.

measure the window opening for window box

Step 2: Cut the Pieces

Cut the two long side pieces and one long bottom piece from 1" x 8" pressure-treated boards to the length determined in Step 1. Cut two square pieces from a 1" x 8" board to form the ends of the box. Rout the top edges of the box pieces for a finished look.

rout top edges of box pieces for finished look

Step 3: Build the Box

Glue, clamp and screw the window box together using 3" galvanized screws. Stain or paint the box before installation if desired. Drill four 1/2" drainage holes along the length of the bottom piece.

drill four drainage holes along bottom piece

Step 4: Install the Window Box

Fabricate or purchase 45-degree window box brackets and mount them to the house using 3" galvanized screws. Use a level to make sure they are even. Position the window box on top of the brackets and attach to the house by screwing through the back panel with 3" galvanized screws.