Many people ask “how to paint a garage floor”.  Your garage floor can be made into something more than just a plain cement dirty area for your cars.  Painting a garage floor takes some effort and time.  Be prepared to spend about four to eight hours on an average floor project.  A garage floor can be painted properly but there is time and effort entailed in the project.  If the floor is prepared properly the paint should stick, but even a thorough application can have problems.

Preparing the Surface
Some of the problems that people experience are probably in part from lack of surface preparation and having a surface that may not be able to receive the paint.  Remember when your car parks in the garage that your tires will be hot from the friction on the ground.  The heat from your tires may pick up the paint in the area it sits, and may pick up as you turn your wheel in the garage.  The quality of the job and the quality of the product applied may be a factor.

Testing your Garage Floor
Your floor should be tested to make sure you can use good epoxy garage floor paint.  If you take a plastic bag cut it into a square and tape it to the floor sealing all four sides, then wait for twenty four hours you may notice moisture trapped underneath.  If you find this moisture you can not use epoxy paint.  You should not use this method in cold weather or in high humidity in the summer, because as your results would not be evident in the cold weather or it may be skewed in the high humidity.  A good time to check with the moisture method is when the humidity is around fifty percent.   Any sealer on your garage floor may prohibit an epoxy coating too. To get the sealer off you have to mechanically etch the surface, because an acid will not work for sealers
Cracks and uneven cement need to be fixed prior to your paint application.  Use the best crack sealer/mortar mix you can buy.  Clean the cracks and apply according to the directions from the manufacturer.  Uneven cement may need to be replaced or just re-leveled.  If there are major cracks or major unevenness in your cement, replacement may be your only option.  If the garage floor has pitting it can be re-leveled with a concrete leveler or called a self leveling floor resurfacer.  If using a good concrete leveler it needs to be applied in warm temperatures and needs to set from 30 to 90 days before any paint is applied. A good time to apply this would be spring or early summer so you can maintain proper cement temperatures and have time to paint
The type of paint is important in painting your floor.  Of you ask any reputable contractor or handyman they will tell you to use epoxy paint only.  It is tough, durable and made for the rough use your garage has on a daily basis.  There are other concrete paints that are not epoxy, but the lifetime on the garage floor is short.
Preparation of your floor should be methodical and precise. Take your time and your floor will be ready to paint. The floor temperature should be over fifty degrees. Follow the recommendations on the product purchased.
Cleaning and Etching the Concrete Floor
Chemicals, oil and grease after years of dripping and work performed in your garage needs to be cleaned thoroughly. With cleaning, acid washing and any other chemical used the fumes with cleaning your garage can be strong; just make sure that the garage is well ventilated.  You can use a good cleaner like TSP and use a brush to clean the cement or use a degreaser and/or cement cleaner to clean the stubborn oily residues.  A pressure washer can be rented to clean any remaining chemicals.  Using a pressure washer after long periods of use can make you sore, so take your time and don’t rush it.  If you want to section off your work you could clean half of your garage, paint it then work on the second half.

Contractors like to use mechanical methods like a scrubber to grind the concrete or a shot blaster to etch the cement, but acids work well too.  The surface of the cement needs to be etched so the surface can be adhered to easily.  Etching works well with an acid if you don’t have a sealer on your concrete, or you are using it for the garage floor only because the fumes for a basement floor maybe overwhelming, otherwise using a shot blaster or a mechanical grinder is the preferred method.  Usually both mechanical methods are and maybe better used by a professional.  Remember to wear protective clothing, because solvents and flying debris can always run the risk of injury and make sure you follow the recommendations of the company that makes the etching compound or cement cleaner.
After all of your hard work in cleaning the floor, it needs to be swept up with a broom and vacuumed making sure that all dust and debris are picked up and especially shortly thereafter  clean up when the acid is used.