How to Buy The Right Concrete Paint

I used to manage a paint store, and one of the most common coatings people asked for was concrete paint. I almost always answered their question with a question of my own - "What kind of concrete are you painting?". I wish there was, but there simply isn't a universal "concrete paint". There's a coating for concrete floors and walls, both exterior and interior, epoxy concrete paint for garage floors, sealers, primers, stains, block fillers...there's a whole lot of concrete paint out there, and half of it isn't technically even paint. I'll walk you through the process of choosing what kind of coatings you need to consider when buying for you next concrete painting project.

Difficulty:

Moderately Easy

Instructions

Things You'll Need

• This article explains the things you need in great detail.

1. For basement walls, you want to look at what is currently on them (if anything), and whether or not you have moisture issues. If there is already a coat of paint on the wall, and it looks to be in good shape, just lightly sand it (fine grit), clean it (Mr. Clean Magic Erasers work great), and paint over it with any interior latex paint. If you're dealing with bare walls, move to step two.

2. For bare basement walls, the most important thing to consider is moisture. Deceptive marketing and infomercials have people very confused - there's no such thing a waterproof concrete paint. There are definitely products that do a fine job resiting low levels of moisture, but if you have anything even slightly significant, you MUST address it before you do any painting (I've seen paint literally pop off the walls). Here's an easy way to tell if you have a moisture problem. Seal a small plastic sheet on your wall by taping around the perimeter, let it stay over night, and check on it in the morning. If it's totally dry, you can get away with a good primer and a latex paint topcoat. If there's very light condensation, I would strongly recommend buying a heavy sealer like Zinsser Watertite or UGL DryLock. If there's heavy condensation or standing droplets in the plastic, you have a leak that concrete paint won't fix - call a plumber or a handyman before you go any further.

3. When painting an interior concrete wall, you'll need some sundries. If you have any holes or cracks in the wall, you'll first need to seal them with a concrete patch. In addition to testing the moisture levels of your base basement walls, you'll also need to clean them. I highly recommend using TSP (Tisodium Phosphate - it's not as nasty as it sounds) coupled with a scrub brush, especially if you have any grease. You'll also need a nylon/polyester for water based paint, and a natural briste for oil, and depending on the roughness of the concrete surface, at least a 1/2" nap roller (soft woven is probably the best material for the money). If you used latex based concrete paint, you can clean your tools with soap and water. If you went with a oil or xylene based coating, you'll need to clean your equipment with mineral spirits.

4. When painting exterior concrete walls, nearly all of the same rules apply, only you'll be using exterior paint instead of interior (though it stinks more, you can use exterior paint inside - just not the other way around). Knock off any loose paint with a heavy putty knife, a scraper, or wire brush before cleaning and painting. Regarding moisture, unless you live in an aquarium, you probably won't have moisture issues stemming from the interior, but things on the outside are generally more dirty. I still recommend using TSP and a scrub brush, but if you can rent or purchase a power washer, you'll find life to be far easier. You may also want to lay plastic covering over you plants, depending on how fragile and close to the wall they are.

5. Regarding concrete floor paint, I have to ask two questions. One, is this going to be interior or exterior, and two, is this for foot traffic or car and heavy machinery traffic. If it's inside and will only be exposed to foot traffic, it shouldn't be to difficult. It's almost like painting a wall, except you're going to be looking for a type of concrete paint called "floor enamel". Nearly every paint distributor carries some kind of floor enamel, and most of the time you'll be able to find a water based product, which is easy to work with. I'd recommend the same cleaning process as before, with the same sundries, only you're guaranteed to need an extension pole with a threaded connector for your roller. Oh, and don't paint yourself into a corner. Don't laugh - I've done it.

6. If you need exterior concrete floor paint for foot traffic, I wold recommend a high gloss, polyurethane based paint (ValSpar makes a good product), or an epoxy designed to withstand the elements. This has to be a very durable coating. It needs to withstand weather, scuffing, and UV rays. Just know that, unless you're incredibly lucky, you'll probably need to apply an additional coat within 2-5 years, depending on your climate. If you're up for the job, you'll need plastic sheets, muriatic acid, a push broom, mineral spirits, a natural bristle brush and roller, and an extension pole. You need the muriatic acid for etching, to give the concrete floor paint something to bite to. You'll need the plastic sheets to cover up anything around the surface, like plants and walls - muriatic acid is nasty stuff. If you absolutely object to acid etching, make sure you do an incredible job cleaning, and know that the coating won't last as long.

7. For a garage or a car port housing an automobile, I highly recommend using an epoxy concrete paint (not technically paint) to combat hot tire pick up. Anything less durable will be a mistake - please believe me. Again, you'll need to acid etch for preparation, and cover your walls with at least 1 mil plastic sheets, three feet up from the floor before you start. You can apply the muriatic acid with a heavy bristle push broom. You can lay down the epoxy with a roller, but plan your day and route ahead of time - once you mix the epoxy, you typically only have 4 hours before it's hardened forever. You can't just put the lid on, and finish tomorrow. If you're into aesthetics (obviously you are) look for garage epoxy that includes color flakes for an added touch.

8. For exterior surfaces subject to hot tires, I would recommend a concrete stain like H&C. In fact, unless you just have to have glossy paint on your patio, I'd really recommend stain for exterior foot traffic surfaces as well. From personal experience, it just holds up better. You still need to acid etch for best performance, but you'll get the best results that will last much longer. If you're worried about the look of stain, H&C, as well as their competition makes dozens of colors available to match nearly any setting.

9. For warehouses and factory floors, I would recommend consulting with an industrial coating sales representative. Major paint companies like Sherwin-Williams have a staff of specialists who deal exclusively in selling products that will stand up to heavy machinery and extreme conditions. This is not the kind of thing of concrete paint that you want to buy at ACE Hardware. I urge you to seek professional consultation - it's usually totally free - they want your business.

Tips & Warnings

• You can use exterior paint on interior surfaces (with a window open), but never the other way around

• Water based products are easier to work with, but oil, polyurethane, and xylene based coatings usually offer greater durability and tighter seals.

• You can paint water based concrete paint over a surface previously painted with oil base, but not the other way around. You can usually tell the difference in the chips. Oil based paint chips of in rigid, brittle pieces, and water based is rubber like.

• Always, always, always, read the instructions of your product, and follow them to a tee. I am a slob in everything else in my life, but you can't afford to be anything short of a perfectionist when it comes to prepping a surface for painting.

• Wear safety goggles and a face mask if you're going to use muriatic acid. It really is nasty stuff.

• If the clerk in the paint store tells you that your product isn't available in a certain color, listen to him. Adding colors formulas that don't belong can drastically effect the performance of your paint, especially on testy concrete surfaces.