The step of cleaning the surface which is going to be painted is pretty easy and critical to an excellent end result. When you read the label on most paint cans you will find disclaimers about how the surface needs to be clean and dry before the paint is applied. The goal is to first clean the surface and then to let it dry. Each is an important step in getting the best adhesion for the primer and the paint which are to follow.

Getting the surface clean is important on both interior and exterior paint jobs. There are several cleaners which are sold and can be mixed with water to create an acceptable cleaning solution. If you do not want to spend money on specialized cleaners any biodegradable dish soap will serve the purpose just fine. Simply mix the cleaning solutions and or soaps in water and start washing.

Some of the culprits you are trying to remove from the surface are dirt, dust, grease, mold, mildew, stains, and oil. Cleaning with just water may not have the ability to take care of these issues, even if applied with a high pressure washer. Soap is engineered to clean so using a little can’t hurt. If you have a serious mold or mildew problem on an interior or exterior surface you should contact your paint retailer for specialized cleaners to deal with these problems.

Cleaning the interior walls can be done with a soft sponge. Cleaning exterior walls will require some kind of soft bristled brush, typically a car cleaning brush that hooks up to a hose is a good option. We do not suggest high pressure washers as they can cause damage to the home if used incorrectly. Once the surface has been cleaned with a sponge and soft soap make sure you thoroughly rinse the surface so as not to leave any soap residue behind. Now you have to let the surface dry. Do not rush this process.  An interior wall washed with a sponge should be given at least a day before primer is applied. Exterior walls where a lot of water and soap have been used may need up to 1 week to completely dry out. Let the surface dry completely. While you are waiting you can complete steps 3 and 4 “removing old/weak paint” and “filling surface imperfections”.

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