How to Build a Window Box

Window boxes add charm and a splash of color to a home's exterior, and they can really boost your curb appeal. This simple woodworking project is ideal for a novice DIYer and can be completed in a day.

By Marian Parsons, Mustard Seed Interiors
Filed under: Curb Appeal, Windows, Handmade, How To

Materials Needed:

3/4" thick cypress or cedar boards
2" x 4" pressure-treated lumber
electric drill
drill bits
2-3/4" concrete screws (for mounting to brick or stone)
1-1/4" exterior wood screws
1-1/4" rust resistant nails
hammer

clamps (optional)
wood filler (optional)
medium-grit sandpaper (optional)
tape measure
2-1/2" sash brush
1 quart primer (oil or latex)
1 quart exterior grade paint (oil or latex, but same as primer)

Cut Boards

Cut 3/4-inch-thick cypress or cedar boards to following dimensions:
8" wide x window length (3)
1 1/4" wide x window length (2)
1 1/4" wide x 5 3/4" long (3)
8" wide x 11" long (2)

Cut 2" x 4" pressure-treated lumber to following dimensions:
8" long pieces (3)

Secure Cleats

Once full of plants and soil, a window box can be very heavy. The best way to mount it is to properly secure it to the exterior wall using cleats. To create cleats, cut three 8-inch pieces of pressure-treated 2x4. Hold the 2x4 tightly against the exterior wall and drill two pilot holes where you'd like screws (Image 2). Drive 2 3/4-inch concrete screws through pilot holes to secure cleat to wall (Image 3). Repeat process on other cleats.

Assemble Front and Back of Box

Place bottom of window box flat on work surface. Stand front of box on end and press tight against side of box bottom. Clamp or hold in place, then drill pilot holes every eight inches using 1/8-inch drill bit (Image 1). Insert 1 1/4-inch screws into pilot holes (Image 2). Remove clamps (if used) and repeat on back side of box.