How to Make and Install an Outdoor Chalkboard

Preparing the Chalkboard

Cut the board to the desired size. Tip: Save yourself some time and trouble and have this cut at the home improvement center. If your board will be in a place where it will rarely get wet, you can use MDF. However, if your board will be in a place where it will frequently get wet, for example on a fence, use hardi-board. 

Add any color flat, latex, exterior paint to a mixing container. Add 2 tablespoons of unsanded grout for every cup of paint. (Image 1) Tip: The unsanded grout will not likely be an exact match to your custom color. Choose a grout that is as close in color as possible. Mix the grout very well to break up any clumps and make the mixture as smooth as possible. Roll the paint on the board generously, passing over the same areas several times to ensure even coverage. (Image 2) If your board will be in a place likely to get wet, paint the hardi-board on both sides with the protective exterior paint. Allow the paint to dry completely before proceeding.

Use a level and chalk line to mark the wall or fence where the top of the chalkboard will go. Get help to hold the chalkboard in place while you attach it to the wall with 2" wood screws. (Image 3) Space the screws no more than a foot apart and about 1 inch from the edge of the chalkboard all the way around the perimeter.

Adding the Trim

Measure and cut trim to fit on the front of the chalkboard, flush with the outside edges of the chalkboard. Paint the trim with exterior white paint or other coordinating color. (Image 1) Attach the trim to the front of the chalkboard with finishing nails. (Image 2) Sink the nails slightly and fill with wood putty. Allow putty to dry and sand. Retouch paint over putty. For high moisture areas, use caulk to seal around the inside of the trim frame. Paint the outside edge of the chalkboard to match the frame.

Curing the Chalkboard

Lightly sand chalkboard with 150 grit sandpaper or finer to remove any bumps and slightly smooth the entire surface. (Image 1) Cover the entire surface of the chalkboard with chalk, using the side of pieces of chalk. (Image 2) Use a chalk eraser to rub the chalk into the surface of the chalkboard. Use a damp sponge to remove the chalk dust before the first use. (Image 3)

Final Touches

Attach a hook and pail to hold chalk while in use. The pail can be removed and taken inside during wet weather.