how to clean garage walls before painting

You love your sunshine yellow walls, but that crayon masterpiece your 2-year-old created might not be your favorite.

Before grabbing a scrubby sponge and your favorite spray cleaner, here's what a professional painter has to say about safely cleaning those colorful walls. It's so simple, you may be surprised!

How to clean latex-painted interior walls

According to Wil Bias, owner of MB Painting and Maintenance Services, LLC, in New Orleans, cleaning walls depends primarily on whether the paint is oil-based or latex. To safely clean latex-painted interior walls, follow these steps.

What you'll need:

Dish detergent
Water
Bucket
Distilled white vinegar
Sponge

What you'll do:

Mix three or four drops of dish detergent in half-filled bucket of water. (Or you can go "old school" and do the cleaning with vinegar: Use two or three tablespoons of distilled white vinegar to a gallon of water. Using vinegar to clean a painted room can be surprisingly effective.)
Wet a sponge in the mixture and wring it out to dry. (This is important as you don't want to mess up your walls with lines of dripping water.)
Wipe off the dirt, rinse the sponge and repeat as needed. This works for all types of latex paint — flat, semi-gloss and gloss.
Make sure the sponge is wrung out dry before cleaning around electrical outlets, light switches and telephone connections. Before cleaning dirty outlet covers, turn off electricity to those areas to avoid shocks.

Bias cautions that you should never use a degreaser or any other harsh chemical cleaners on latex-painted walls.

"If marks don't come off using just soap and water or white vinegar and water, you'll have to repaint."

How to clean oil-based painted interior walls

Because oil-based paints are a bit hardier, in addition to using the detergent or vinegar and water mixture, you can safely use a mild degreaser to remove grease, especially on kitchen walls.

What you'll need:

Dish detergent
Water
Bucket
Distilled white vinegar
Sponge
Mild degreaser

What you'll do:

Follow the instructions for latex walls above.
Follow the instructions on the degreaser's packaging to safely use it to get rid of any grease or buildup on the walls in the kitchen.

As with latex-painted walls, never use a scrubby sponge, Teflon pad or harsh chemicals to clean walls painted with oil-based paints. "If you do, you'll leave permanent streak marks every place you wipe," Bias said.

And, of course, follow the above precautions when cleaning around electrical and phone outlets.

How to clean exterior walls

To clean exterior painted walls, whether latex or oil-based, follow these steps.

What you'll need:

Garden hose
Pump garden sprayer
Jomax
Bleach
Water
Soft scrubbing brush
Optional: Pressure washer

What you'll do:

Start by wetting the walls.
Then, using a pump garden sprayer, lightly spray the walls with a mixture of 1/2 cup Jomax, 1 cup of bleach and enough water to fill the container.
Allow the mixture to work for 15 minutes, then scrub with a soft-scrubbing brush. This will remove mildew, mold and other dirt.
Rinse with a garden hose.

When cleaning a two-story house, a garden hose may not reach high enough to completely rinse the walls. In that case, you can use a pressure washer but only if it's fitted with a 25-degree nozzle and you don't use pressure. Just spray the water as it comes out. Using pressure could damage the paint and cut into the siding.

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This article was originally published on Sep. 17, 2015.