Metal lath is used in stucco installation to add support to the process. Stucco is hard to get to stick to a surface without something else in place. Using metal lath is the most popular and cost effective solution to this.
1. Set Up the Sheathing
Stucco is going to require a base as well as the metal lath. You can use a standard plywood sheathing since it won't be seen once the stucco is applied. Attach the plywood to the exterior surface using brackets and bolts.
2. Add a Moisture Barrier
The first thing that you are going to have to do to make sure that you are ready for the job is to get your moisture proof barrier installed. This is something that you will apply directly to your wood sheathing. With this barrier, you will be able to no longer have to worry about wood decay.
Wood decay is something that will happen whenever there is wet concrete or plaster that is applied to the area. It is a good idea for you to check the building codes in your area so that you can get the correct type of material for the barrier.
Once the sheathing is in place you want to use building paper over it. This will create a waterproof area to work with. The paper should overlay at the seams by at least two inches to prevent moisture from bleeding through. You can use a staple gun to attach the paper.
3. Apply Beads and Edges
Once you have your moisture barrier where it needs to go you will then be able to begin work on installing your casing beads, weep edges and corner beads. You will also need to make sure that you install your expansion joints as well. Whenever you are applying your lath accessories you will need to make sure that you either staple or nail them into place about every foot and a half. If the type of lath that you are using is not self furring, then make sure that you have furring strips that are nailed into place once everything else has been applied.
4. Hang the Lath Horizontally
With the sheathing in place and papered you can work on the lath. Use two inch nails to attach the mesh to the sheathing layer. The mesh needs to be overlapped at the seams just as the paper was. You also want to nail in the lath every 16 inches, both horizontally and vertically to create more support.
You will need to make sure that your metal lath is hung horizontally. The joints that are made between each of your panels need to be laid in a type of a brick pattern. The seam that you use between your first and second panels that go on the bottom of your wall need to fall right in the middle of your panel. You will then put them directly above them immediately following this.
5. Apply Mesh
Your metal lath that is expanded will come with a mesh that is diamond shaped. For you to be able to have a proper holding base for your plaster or stucco, the pockets that are formed by your mesh need to face up. The mesh that you are using needs to feel rough whenever your run your hand down it and smooth when you run your hand up it.
6. Finish up
Make sure that you attach the lath with roofing nails that are 16 inches. Cut your lath with shears, a circular saw will be necessary for a bigger job.
7. Apply Stucco
Now you're ready to get your stucco on!