How to Lath & Plaster

Attach wood laths to the wall frame horizontally, approximately 1/2-inch apart. The wooden laths should be about 3/4- to 1-inch wide, 1/4-inch thick and 4 feet long. Tack them to the wall frame with hammer and nails, covering it completely, starting from the bottom and working to the top. Leave 1/2-inch of space between each lath for the plaster to sink into. On the side of the wall that is not smooth, the plaster forms hooks between the laths, holding it securely in place.

Mix the sand-based plaster per manufacturer’s instructions or purchase pre-mixed plaster to save time. Use a smooth trowel to apply a layer of the plaster over the lathed wall. The plaster should be about 1/4-inch thick. Scoop the plaster onto the trowel and smooth it onto the wall, pressing it between the laths to form the hooks. Continue the process until you have covered the entire wall in a roughly even layer of plaster. Allow the plaster to dry for 24 hours.

Apply a second layer of plaster to the wall, creating an even finish. Scoop the plaster up with the trowel and smooth it onto the wall. This second layer should be approximately 1/2-inch thick. Allow the plaster to dry for 24 hours and repeat the process with a third and final 1/4-inch thick layer of plaster. The final layer of plaster should dry for at least 48 hours before doing anything that could damage or disturb it.