Stucco application looks terrible if it’s not done properly. The correct process for stucco actually isn’t all that difficult. It just needs to be done the right way. For stucco application over wood, there are a number of stages to a successful stucco application. Be certain to follow them for the best results.
Step 1 - Add Felt
You can’t apply stucco directly on to the wood. The wood needs to be properly covered so it can support and take the weight of the mortar used for stucco.
Begin by nailing 15-pound roofing felt on to the wood. Begin at the bottom of the wall and overlap each top edge as you move up the surface. Continue until all the wood has been covered by the felt.
Step 2 - Use Netting
To help the mortar adhere properly, you next need to cover the roofing felt with 17 gauge metal netting. This generally comes in rolls that are 150 feet long. Cut where needed and nail it over the felt. Use galvanized roofing nails to attach the netting to the felt.
Step 3 - Add a Scratch Coat
At this point, you’re ready to begin the proper stucco application. Mix up a large batch of mortar mix and start to apply it over the felt and metal netting. This first coat, or scratch coat, will give a firm base for the stucco. It needs to be between ¼ inch and ½ inch thick, and you should use the trowel to work it firmly into the netting. The mortar itself should stick out through the netting, which acts as a solid base to hold the drying mortar in place.
Allow the mortar to dry slightly. Don’t wait until it’s almost completely dry. Take your plaster’s rake and score through the mortar to a depth of around 1/8 inch. Be sure you complete a wall before moving on to the next one.
Step 4 - Cure
Now you need to give the mortar ample time to dry, about 48 hours ought to do it. During this period you need to mist the mortar on the wall every so often to keep the dampness in it. If you’re working in the middle of a hot, dry summer the misting will need to be more regular.
Step 5 - Add a Final Coat
Once the curing of the scratch coat is complete, the final coat of the stucco application can begin. Use the flat finishing trowel and a thin coat of mortar, about 1/8 inch to 1/4 inch thick. If you plan on having color in the stucco, mix up the pigment fully before adding to the mortar and then stir it so it’s completely combined.
Once the mortar has been applied you can use the plasterer’s rake to finish the stucco to the texture you want. Give the finish coat a few days to cure, misting it periodically. If you plan on painting the stucco, wait six weeks before doing so.