Preparation

• Preparation work must be completed before painting concrete. All dirt or oil must be sand or power washed away. Concrete is porous, and when there is soil behind it, as in a retaining wall, moisture will gradually work through it to the open side. Sealing the concrete with a moisture barrier pre-paint sealer prevents the water from bubbling under any paint.
  
  

Latex Paint

• Outdoor paint needs to stand up to weather, heat and the highly destructive direct sunlight rays. Latex paint for concrete goes on easily but usually begins to fade, crack and peel after a few years. Repainting the latex requires that all the previous paint be taken off, either by scraping it or sandblasting. Sealing the latex with a clear sealer over the top coat gives a measure of protection which makes it last longer.
  
  

Epoxy Paint

• Epoxy paint for concrete is more often used on walks and driveways than walls and foundations. It forms a durable, long-lasting coat that is somewhat shiny in appearance. Epoxy paint is usually found in industrial settings or shopping centers where a concrete floor takes daily abuse. In the home it is usually reserved for basements but can also be used in patios or other places where heavy foot traffic is expected.
  
  

Polyurethane Stain

• Polyurethane is a stain that is used the same as a concrete paint. Like all paint, it comes in a variety of colors. Similar to epoxy, it lasts a long time and is not often used in residential applications. Polyurethane is very glossy, and, when it gets wet, it provides little traction. If it is used along a wall, this is not a problem, but when using it where foot or vehicular traffic is found, it requires a non-skid additive mixed in before applying that gives it a less-slick feel.
  
  

Vinyl Enamel

• Steve Thomas of "This Old House" recommends using vinyl enamel, a swimming pool paint for exterior concrete use. It lasts longer than latex paint and goes on as easy. The concrete surface must first be washed with trisodium phosphate and then rinsed and dried.