Spray painting your home can be a daunting task if you don't know how to work the spray gun. And, depending on the size of your job or even the type of job you want to complete, you may want to consider sticking with rolling or even hiring a contractor to complete your house painting job.
Spraying vs. rolling
There is a bit of technique and skill required in both spraying and rolling. More often, for amateurs, spraying is used only on the exterior of the home. With indoor spraying, above average skill is needed to properly paint the home. A painting contractor is recommended.
Rolling takes more time, but can have a crisper, more complete look without the skills needed to properly utilize the spray machines. A multiple hour job using a sprayer may take multiple days with a roller. However, a job done right is certainly quicker than redoing a job that's been done incorrectly.
Prepping a house for painting
Whether you're spraying or rolling, you should properly prepare your home for painting. You'll need to scrape your area to be painted in order to remove flaking paint. You also may want to sand the area in order to create a more perfect smooth surface for painting.
Next, you'll want to prime your walls. Depending on the type of paint you'll be using, you'll want to use the appropriate type of primer: latex for latex paint and solvent-thinned primers for solvent-thinned paints. Also, if you're painting metal, be sure to use a primer specifically made for metal.
If you're painting the exterior of your home, you'll also want to remove any home accessories, such as numbers, shutters and mailboxes. Likewise, light switch plates and the like will need to be removed in order to prepare for painting indoors.
Next, you'll want to wash the surface to be painted in order to clear away any debris and reset any popped nails, particularly if painting your home's exterior. You'll then want to prep interior walls with painter's tape and cover any large areas you don't want painted with tarps. Similarly, if painting your exterior, you'll want to cover shrubbery and porch flooring you don't want covered in drips.
After all this prep work is complete, if you've chosen to spray paint, you'll need to know how to choose the sprayer right for your job.
Choosing a sprayer
There are basically two types of sprayers in the house painting world: those that use air and those that don't.
Airless sprayers have extreme pressure near the tip. So if you're uncomfortable with the dangers this may impose (any body part that nears this tip during operation could have paint injected into it), you may want to choose an air sprayer or have a contractor spray your home.
If you choose to spray yourself using an airless sprayer and receive such an injury, you'll need immediate medical attention for the injection wound.
In general, a piston pump sprayer or diaphragm pump are usually best for house painting. Diaphragms can have more overspray. If you're not a professional painter, you'll likely want to rent a high-quality sprayer for your painting jobs.
How to use a spray painter
Once you've rented a sprayer, you'll want to make sure the area near your paint job is properly taped, tarped and sealed. You'll want to seal off your room because paint can drift through the air to unexpected places if not sealed off. If you're painting outside, NEVER spray on a windy day and be sure to cover everything outside you don't want painted (e.g. cars, fences, shrubs).
Now you'll need to pour paint into the sprayer's tub and thin the paint as recommended by the sprayer's manufacturer.
Now you must understand the correct technique for spray painting. Once you've covered yourself with long sleeves and pants or a paint jumpsuit (a respirator is also recommended since you'll want to avoid breathing in paint), start spraying from the top corner down. Your painting "strokes" need to be smooth and steady, working down to the bottom corners.
Try not to create thick layers of paint from too much overlapping, and be sure to steadily and slowly cover the areas so as not to end up with uneven coats. You're better off with several light coats than one sloppy, uneven coat.
Now you're on to the least fun part of your project--cleaning your sprayer. If it weren't for clean-up, painting with a sprayer would be much more efficient for small jobs. As it is, you're better off buying a can of spray paint for small paint projects to avoid the clean-up duty.
You'll want to follow the manufacturer's or rental agent's guide to cleaning the spray gun properly. You can lose your deposit and ruin the gun if it's not cleaned well or in time.