I Have A White Stain On My Garage Floor

This will allow the moisture in the concrete to rise to the surface and evaporate leaving behind the salts that cause the whitish discoloration.

I have a white stain on my garage floor.

Cover the stain with a thin layer of cat litter and brush it in. A white powery residue appears on garage floor after the floor gets wets. The calcium hydroxide further reacts with carbon dioxide in the atmosphere to form calcium carbonate which is the white dusty material you commonly see on the surface of concrete this is called efflorescence. Wait 60 days before attempting to remove any white stains on new concrete.

These can be removed along with the rust stains with a good power washing and some scrubbing with a stiff bristled brush. Allow new concrete to cure completely. It usually gets wet from driving a wet car into the garage during a rain or when hosing the floor down. Rarely will it cause a problem inside of your garage.

It can become heavy enough that you may need to clean it off. The white spots are most likely efflorescence minerals that are carried to the surface by the moisture vapor escaping up through the concrete from the subgrade. There is no basement in this house and no plumbing goes under the garage floor. It s a very common problem in cold climates on garage floors.

Sweep up the litter and pour cola to cover the area. The residue is typically in the center of the garage. The house was built in 1975. Efflorescence is a white powder created when saltwater evaporates from a masonry surface like concrete.