Spraying stucco and hand applying stucco are two very different application processes and they do require a little bit different technique. Either method will have its own pros and cons, just like everything else but you should be aware of some of the pitfalls and advantages of each method because one method is going to work a little bit better for some people, depending on your skill level and what type of material you are actually applying.
Spraying stucco can work for the base coats as well as the finish coat but it's probably more common when it comes to applying the finish coat of the stucco process because it goes on much thinner than the base coats and you can achieve a much more consistent and uniform amount of material on the wall if it is spray applied, especially convenient if you are a novice.
Spraying VS Hand Spreading It:
There are several factors that you should look at when deciding to hand spread or spray on the stucco to the walls. These are things like the skill of the applicator, the cost of the tools needed, time, access and other critical points.
The Skill Of The Applicator: Most plasterers don't mind hand applying either base coats or finish coats but they are familiar with the wrist movements, pressure and other factors that come into play when hand spreading. Oftentimes, a plasterer may prefer to hand spread because it is a lot less tools that are needed, is cleaner and is faster in some cases, if the area they are spreading is a smaller one.
On the other hand, a novice who has never spread before or has limited experience will find the process very difficult and messy, time consuming and sometimes even frustrating. Spraying the stucco on will be much faster and will essentially take a lot of the "required" skill that it takes to get the mud to stick to the wall out of the entire process.
The Tools Needed: It may be obvious that if you plan on spraying the stucco on, it will be a significantly larger investment than if you chose to hand spread the material on the wall.
Even if you plan to spray the stucco on the wall, you will still need the other tools (hock, trowels, a scratcher, floats, etc.) in order to work the material onto the wall. The sprayer is basically intended to get the mud "on the wall" when it comes to base coats and can be used as a finish if properly sprayed using a finish material.
- Hand Spreading: If you plan on hand spreading the mud onto the wall, you will need all of the required hand tools like trowels, hocks, scratchers (if doing a three coat system), green floats, hard rubber floats, etc.
These are the basic hand tools you will need for applying the mud to the wall. Other items like a mud board, mud board stand, wheelbarrow, shovel, mixer, etc. will also have to be used in order to transport the material from the mixer to the wall.
- Spraying: You will need basically everything you would need if you were hand spreading, plus a compressor and a sprayer. The compressor will usually have to be a pretty decent model that has a relatively high cfm output to keep up with the sprayer, especially if you are spraying base coat materials.
If you only plan on spraying finish materials and not base coats, then a smaller compressor can be used and a different sprayer will also work better, which we will dive into a little bit more in this article.
The Time Difference: When comparing the amount of time it would take to hand spread vs spray on stucco, it is full of variables but taking a look at some of the basic elements associated with each process will help you understand some of these variables better.
- Setup Time: The amount of time it takes to setup the compressor and sprayer will be added time that you would not have to put in if you were hand spreading.
The "initial setup time" will be close to the same and is necessary when hand applying or spraying which includes things like mixing the mud, transporting it over to the work area, etc.
- Making sure that the mud is the proper viscosity to flow through the sprayer, hooking up the compressor, hoses and sprayer together and setting a good spray pattern are three things that will take additional time when choosing to spray the stucco on.
Desired Finish/Texture: Coming Soon!
Spraying Base Coat Materials:
When it comes to spraying the base coats of Stucco, you will probably find that a mortar sprayer with a larger compressor, like the ones you can find online are probably going to be the best bet but do require a pretty substantial upfront cost investment, even if you rent the compressor and by the sprayer itself.
Sprayers For Base Coats: The sprayers that are capable of spraying stucco base coat materials (examples shown here) use much more air (around 9 - 12 cfm @ 100psi., usually) and will require a more expensive compressor, like this one here.
They have smaller hopper capacities and larger holes where the materials comes out, which is why they need more air.
These can spray base coat materials that tend to be a little thicker than finish coat materials and are able to let the mud stack up to the standard 3/8" - 1/2" thickness that is usually needed for base coats.
Spraying Finish Coat Materials:
The finish sprayers will be much less expensive and will be easier to find, as they are available at most home improvement stores and online. These will have a little bit different design to them and will have major differences in the hopper, the orifice and the required amount of air that is they require.
Sprayers For Finish Coats: Sprayers that are better suited for spraying finish coats are different than those the other types, which you can see from the pictures. These will usually be much less expensive and need much less air to operate (around 5 - 8 cfm).
The hoppers are usually a little bit larger and are usually made from some sort of plastic material, rather than metal.
Since finish coat materials go on a lot thinner (1/16" - 1/8"), the orifice on the nozzle is a lot smaller and is always going to have a single hole, rather than multiple. These can apply the material to the wall in a very even consistency and can be left alone and is referred to as a dash finish or it can be used to apply the material to the wall and then spread around to achieve a different texture.
The example hopper gun shown above is only one type of style and they can look a little different but use the same basic principles to spray the material on the wall.
Hand Spreading Stucco...
Hand applying stucco has it's own challenges, to say the least and it is something that novices can do but it will take much longer to get a wall done and chances are that the final product will be on the rougher side, if you are not careful. Having an experienced plasterer on hand would really benefit you but is not always an option, so you will need to be mindful of a couple of things.
Some Of The Hardest Aspects Of Hand Spreading:
There are a couple of aspects to hand spreading stucco that make the process much harder to do, when compared to spraying it on and these are:
- Taking The Mud Off Of Your Hock: Typically a hock and trowel will be used to spread the base coat and finish coats of the stucco onto the walls but taking the material off of your hock proves to be the hardest part of the process for beginners. You will likely make a mess and drop quite a bit when trying to take material off of your hock and loading your trowel up.
- Applying The Mud To The Wall: Another very difficult part of the process for beginners is actually applying the material to the wall. This applies more to the base coat(s), than the finish coats because you have to apply more material on the wall and the pressure used to get the amount of material to stick will be a little lighter.
- Getting The Proper Depth: When applying the brown coat, it will be hard for most people to get the proper depth on the wall. You have your grounds that will give you the thickness you need (weep screed, plaster stop, windows, doors, etc.) but if you are several feet from any stucco grounds, then it is hard to get the right thickness without having too much or too little material on the wall.
Scratch coat is a bit easier because you simply want to cover the wire (furred), so you know how thick you need to go and finish coat is applied at 1/16" - 1/8" thick so you are basically just covering the brown coat and is also easier to do.