Asked by: Neva Zekhnini
asked in category: General Last Updated: 30th January, 2020

Why is my dark grout turning white?

Grout turning white can be caused by efflorescence which is the calcium from the water and the underlying concrete or mortar migrating up through the porous cementitious grout. Excessive efflorescence is considered a symptom of an excessive moisture problem.

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Also know, how do you clean black grout that has turned white?

Avoid using bleach or peroxide on dark grout because it will cause discoloration and can weaken the grout. A solution of half water and half vinegar is also effective at cleaning both dark grout and white floor grout. Fill a spray bottle with the solution and apply directly to the grout.

Secondly, what causes grout to change color? The main cause for this variation in color is uneven drying of the Portland cement in the grout. There are jobsite conditions and factors which create the conditions for uneven drying and improper cement hydration. Like colored grout, this is mainly due to the uneven drying of the cement.

Similarly one may ask, how do you remove efflorescence from grout?

Moisten the grout with clean water and try scrubbing the efflorescence using a clean stiff nylon brush and/or a clean white nylon scrubpad. Avoid soaking the area with excessive amounts of water. In mild cases of efflorescence, this process will remove the powdery salt residue from the surface of the grout.

Why is my black grout turning gray?

The problem you have is called efflorescence which occurs when any concrete product is over washed before it is cured. They have an efflorescence remover on the market, but they only work so well with grout. Make sure that you get a good sealer onto that grout before you get after it again with water.

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