How to Clean Bricks and Mortar With Muriatic Acid

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Things You'll Need

  • Muriatic acid

  • Bucket

  • Water

  • Eye protection

  • Thick rubber gloves

  • Ventilator mask

  • Plastic drop cloth

  • Clean cloths (3)

  • Stiff-bristled brush

  • Ammonia

  • Baking soda


Muriatic acid can kill plants. If you are working near greenery, spray water over the plants to protect them from the acid. Have a baking soda and water nearby to neutralize the acid if it comes into contact with plants. Be sure to have adequate ventilation such as fan. Always add the acid to the water when mixing. Adding water to acid can create a serious heat reaction and cause the mixture to erupt and spray. Do not mix muriatic acid with other chemicals, as it could cause dangerous reactions.

Clean Bricks and Mortar With Muriatic Acid
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Efflorescence is a common occurrence on new brick and mortar. This is a flakey white deposit that occurs when the moisture within the bricks and mortar comes to the surface. The liquid combines with additional minerals within the masonry. When the moisture dries, it leaves behind mineral deposits on the outside surfaces. Once the humidity level in the masonry is gone, efflorescence stops. However, the white deposits are still apparent until they are cleaned off. The fastest way to clean efflorescence from bricks and mortar is using a muriatic acid cleaning mixture.


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Step 1

Cover surrounding area with a plastic drop cloth to protect surfaces.

Step 2

Put on thick rubber gloves, a ventilator mask and eye protection.

Step 3

Mix 10 parts water to 1 part muriatic acid in a bucket.


Step 4

Apply water to the bricks and mortar with a cloth until damp.

Step 5

Saturate a cloth in the acid and water mixture and apply liberally to the bricks and mortar.

Step 6

Allow mixture to sit about one minute.


Step 7

Neutralize the muriatic acid by applying a mixture of ammonia (1 cup) and water (1 gallon) with a clean cloth.

Step 8

Wash with a stiff-bristled brush and water until the residue is removed from wall.