Painting a floor is a task that can be tackled by a determined DIYer with just a little bit of experience. With that said, there are a few common difficulties that you might find yourself running into. Let’s see if we can anticipate a few of them and give you a finish that you might be happy with in the long term.
Contamination
If the surface you’re painting onto is greasy or dusty, then the paint will have difficulty adhering to it. This will result in flaking and other, related problems. If you’re painting a floor, then this is especially troubling, because lots of dust will settle and anyone walking over the floor will distribute plenty of debris and dirt.
There are two ways you can deal with this. The first is to thoroughly sweep and jet-wash the floor before you get started. This should be considered an obligatory first step in any floor-painting exercise.
The second concerns your choice of paint. Epoxy ester-based floor paint tends to help to create a smoother surface and a better finish in general.
Adhesion
A related problem comes from an insufficiently smooth surface. Concrete tends to come with lots of little hills and valleys, cracks, and pits, where paint can collect. This will cause it to dry unevenly, which in turn will cause stretching and splits. You can either use a pour-over floor smoother to deal with the problem, or you can sand the floor until it’s just about level. In either case, you’ll want to clean the surface before you break out the paint roller.
Damp
If your surface is moist as you’re putting the paint on, then you might find that the moisture becomes trapped. Most manufacturers will advise that you leave a surface to dry after you’ve washed it (or put it down initially) – ideally for a month or more. Don’t rely on guesswork – get a moisture meter and check unless you want to be painting the floor multiple times.
Preparation
If you’re doing this for the first time, then there’s a more obvious risk to consider: that you might paint the floor such that you can’t actually get out of the room without standing on wet paint. This embarrassing problem is actually completely avoidable: just make sure that you know how you’re getting out, and that you paint the far side of the room first.
Lack of Ventilation
If you’re going to be painting, then you need to ensure that the fumes have a way to escape – especially if your paint contains volatile organic compounds. Open windows – but make sure that there are screens in place to prevent dust from blowing inside onto your nice, clean floor.