How do you paint a concrete floor?

It’s easier than you think to add some colour to a boring, grey floor. Follow this seven-step process to paint a concrete floor. Take note of what you need to complete this project below:

What you need

• Bucket, soapy water and mop (indoor)
• Power washer, detergent and stiff broom (outdoor)
• Degreaser
• Power sander
• Sandpaper
• Vacuum cleaner
• Cloth
• Concrete patch / masonry filler
• Trowel
• Masonry sealer
• Masonry primer
• Paint roller
• Paint brush
• Masonry paint

1. Wash it

First up, give your concrete floor a good wash down. Start by sweeping away any dust and debris. If your concrete floor is indoors and polished then simply fill a bucket with some soapy water and mop the whole area. After applying the mild cleaner to the floor, rinse with clean water. For outside concrete floors, a power washer is most effective. Pour a detergent over the floor and use a stiff broom to give it a thorough clean. Then blast all the dirt and grime away with the pressure washer. It is also advisable to scrub the floors, whether indoors or outdoors, with a degreaser. You can also etch the floor with a rust remover and / or concrete etcher. The cleaner the surface is, the better the paint coating later on in the process.

2. Sand it down

You must make sure the concrete floor is completely dry after washing it. If there are any signs of water seepage, this must be sorted out before beginning the project, otherwise you will only run into damp problems down the line. Once you are sure the area is dry, you can sand it down using a power sander. During this process you need to ensure old paint is removed and lumps of concrete are sanded down. The aim is to get an even, smooth surface. After you have sanded the floor, you will need to vacuum the floor and then wipe it with a cloth to remove all residue and and efflorescence – the white powder-like crystalline deposit that sometimes develops on damp on surfaces of masonry, stucco or concrete.

3. Fix it up

After sanding the floor, you will most likely find a few places that need to be filled to get the desired surface. If the floor is very rough, and if there are very big holes, then you may need to use concrete patch. Minor defects, such as small holes and cracks, can be repaired using a masonry filler. Use a trowel to smooth out all the defects. Follow the package instructions carefully and make sure you let it dry before moving on to the next step in the project. It’s important to make the floor as smooth as possible so that moisture cannot peel the paint off the concrete floor.

4. Seal it

Applying a sealer before priming and painting the floor will also help prevent moisture seeping through the floor and peeling the paint off. There is no use rushing the project, so apply two, or even three, coats of sealer. Use a paint roller for the most of the job, and a paint brush to get into the corners. Tape is always handy to make sure you paint in the lines. Always make sure you allow enough time for each coat to dry.

5. Prime it

Now it is time to get the floor ready for the paint. Apply a concrete bonding primer to the floor surface, also using a paint roller and paint brush. The masonry primer will help make the paint stick to the floor, so it is an important step in the process. Depending on the circumstances, you may like to do two coats of primer. If you do, just make sure each coat is completely dry before applying another.

6. Paint it

This is the step that you have been preparing to get to. Double check that you have purchased masonry paint because it is specially formulated to expand and contract with the temperature changes of concrete. Do some colour research before application and find a colour combination that you think will work best for the specific floor.You can use a paint roller or paint compressor, with a paint brush for the tighter spaces. Leave the surface to dry at least twenty-four hours before applying a second coat of paint.

7. Seal it again

For a superior finish it is a good idea to seal the concrete floor again after painting it. Remember to allow the surface to dry completely between coats. Once it is dry, enjoy! You can move furniture or other objects onto the floor and allow people to walk on your new, bright and beautifully painted concrete floor.

You may not have time to do this yourself, so why not get a painter in to help you with this project? Remember to ask them five important questions before they begin.