New application techniques for stucco exteriors give this traditional coating a new look and allow the do-it-yourselfer to apply spray stucco in a short amount of time. You can still achieve the traditional look of stucco walls, but the new spray stucco has different components that allow it to stand up to all types of weather for many years.
Prepare the House for the Stucco Exterior
To get spray stucco to adhere to the house, you need to have a base. For a wood frame house, the house needs to have a layer of water barrier paper wrapped around it. You can skip this step for a masonry or brick structure.
There also needs to be a layer of metal lath in place around the house. This mesh material helps bind the stucco to the wall and helps to keep the spray stucco from dripping off the wall before the stucco dries. Overlap the metal lath mesh seams both horizontally and vertically. Nail the mesh on both sides of corners. Be sure to nail the metal lath to studs and not just to the wooden sheathing underneath it.
Practice Applying Spray Stucco
Set up an old piece of plywood. Prop it in a vertical position. Mix the spray stucco mixture. Hook up your stucco sprayer to the air compressor. Put on your safety goggles to protect your eyes against stucco rebound.
Pull the nozzle on the stucco sprayer and aim it at the plywood. It doesn’t take long to figure out if your stucco is too soupy and needs thickening. You can also determine how quickly to move your sprayer to get the best coverage. Even though the board doesn’t have the metal mesh in place, you can still get a good feel for the stucco application process.
Apply Spray Stucco
Set up the work zone. To apply the stucco efficiently, you need someone mixing the stucco, another person bringing the stucco close to the sprayer in a wheelbarrow and a third person applying the stucco to the house with the sprayer. If you are spraying higher than seven feet, use scaffolding on wheels to easily move from one part of the house to another.
Begin your spray application on a back wall. Even though you may experience with spray stucco, it’s best to work out any problems on an inconspicuous wall.
Load the sprayer from the mixed batch with a gallon container. You can also dip the sprayer right into the batch of stucco mix to load it.
Hold the sprayer about 12 inches perpendicular to the wall. It’s important that you keep the sprayer moving at all times. The first coat should just cover the metal lath and should be the same depth. Use a trowel to level out uneven spots.
Allow the first coating to set. Scratch it with trowels to give the second coat a good surface to adhere to.
As soon as possible apply the second coat of stucco. Keep this final layer as smooth and level as possible. If necessary use a trowel to level the depth of stucco on the walls. Clean up any excess stucco that dropped on the foundation or ground as you were applying it.