How to treat efflorescence on interior walls?

Author: Esther Witting PhD  |  Last update: Thursday, July 3, 2025

Some of the best ways to remove efflorescence include:
  1. Pressurized water: Applying pressurized water may dissolve efflorescence quickly. ...
  2. Diluted vinegar: If you're in a pinch, household diluted white vinegar can be used on efflorescence. ...
  3. Brushing: With a strong brush, you can remove efflorescence with ease.

How do you stop efflorescence on internal walls?

You can treat efflorescence on internal walls using a special product called salt neutraliser. This product is designed to stop the salts reacting with water and can be used on bare plaster, stone, brick or render – not over paint or wallpaper.

What paint stops efflorescence on interior walls?

It's a painting issue that's easily overcome by the use of Zinsser Watertite®.

How do I permanently get rid of efflorescence?

Once the water source is eliminated, most efflorescence (also called Calcium Carbonate or limestone) can be removed with abrasive techniques. Dry brushing, light water blasting or light sandblasting followed by flushing with clean water. In large areas, rotary scrubbers with scrubbing pads may also be used.

How to fix efflorescence inside a house?

You can remove efflorescence relatively easily with high water pressure (spray) or with acids such as muratic acid. Products such as CLR or Lime-Away can work too if used with water and a brush... These will keep moisture from seeping through the wall and evaoporating, leaving behind efflorescence.

Efflorescence Tips and Tricks

Will drylock prevent efflorescence?

The application of DRYLOK® Wet Wall Bonding Primer will minimize the reoccurrence of efflorescence when the surface is properly treated. Patch all holes and cracks with DRYLOK® Fast Plug®.

Does vinegar neutralize efflorescence?

The acidity in the vinegar helps remove the efflorescence and calcium deposits by breaking down mineral crystals. After cleaning the surface, let dry for 48-72 hours (moisture content below 25%). The second (and easier!) method of cleaning is using RainguardPro Restore-N-Prep.

How do I stop efflorescence returning?

Clear water repellents, silicone and acrylic coatings also may help you remove efflorescence as well. The coating will absorb water across a masonry surface and prevent efflorescence from recurring. Plus, the combination of warm water and white wine vinegar has been shown to eliminate efflorescence.

Can CLR remove efflorescence?

We were told a diluted CLR solution would work. We tried this and it was a lot of work to scrub the surface clean of the residue and you have to be sure to rinse immediately because technically CLR is not for painted surfaces.

What causes efflorescence indoors?

CAUSES OF EFFLORESCENCE

Simply stated, efflorescence occurs when water containing dissolved salts is brought to the surface of masonry, the water evaporates and the salts are left on the surface.

Can you just paint over efflorescence?

Painted surfaces already damaged by efflorescence must NOT be repainted until the source of the moisture is identified and eliminated or blocked (by waterproofing). It may be necessary to engage the services of a qualified waterproofing specialist.

Can you drywall over efflorescence?

If it disappears when sprayed with water, it's efflorescence. As noted in the article above, this indicates water is moving through the concrete wall. Do not cover this wall with insulation, framing or sheetrock without addressing this moisture issue.

What is the best sealer for efflorescence?

In these cases, water repellency is critically important. In these situations, use LastiSeal Brick & Concrete Sealer for an unbeatable 15-years of protection, or go for DryWay Water-Repellent Sealer, which is a DOT approved silane/siloxane water-repellent. Efflorescence is a very common and controllable condition.

Will efflorescence eventually stop?

In all but very extreme cases, efflorescence will stop as capillaries in the stone become blocked by crystallized salts. Once the process stops, the white deposits will eventually wear off with use and exposure.

What is the white powder on my internal walls?

Efflorescence appears when water evaporates from the wall. They have a crystalised, chalky appearance and feel grainy to touch. Salt efflorescence on internal walls is made up of a mix of chemicals such as calcium carbonate, sodium and potassium.

What is the best solution for efflorescence?

A stiff scrubbing brush and a dry brushing technique will remove the efflorescence. Muriatic acid can be used for efflorescence removal, but it poses risks such as discolouration and potential surface damage. Consider safer commercial solutions.

How to get rid of efflorescence on internal walls?

Using Brush

As mentioned, wall salts are soft and powdery in texture which means they can be removed easily. If the efflorescence developed in your interior walls, it is best to use a brush with stiff—or even soft—bristles.

What happens if you leave CLR on too long?

If CLR Grease & Oil Remover is left on a surface for too long it begins to dry and can be very difficult to remove.

Can efflorescence be removed permanently?

How do I permanently get rid of it? If you wish to remove efflorescence, you can consider using a specialized efflorescence remover. These products are specifically formulated to dissolve efflorescence and remove dirt from paving stones and concrete surfaces without causing discoloration or damage.

What neutralizes efflorescence?

You will still use hydrochloric acid to eat away the efflorescence however because the tile is super porous you need to be mindful to ensure that surface is sufficiently wet not just before you apply the acid but during the application as stone and concrete will start absorbing the water initially applied which will ...

Does vinegar fix efflorescence?

Next you should rinse the pavers with 6% vinegar. Vinegar is extremely effective against removing efflorescence from any surface, whether it be interlocking pavers, concrete pavers or bricks. You also do not have to worry about rinsing dangerous acids into the soil around your pavers.

Can I paint drylok over efflorescence?

The white powdery substance is efflorescence, and you want to neutralize it with DRYLOK Etch which is much safer than muriatic acid. Above all, remove efflorescence prior to waterproofing to avoid the waterproofer from failing.

What chemical cleaner is good for efflorescence?

Smartseal Brick Acid Cleaner - Easy To Apply Effective Brick Cleaner Solution For Exterior Brick Walls and Masonry Surfaces - Removes Efflorescence, Dirt, Grime & Limescale (5 Litres)

Will lemon juice remove efflorescence?

Similar to vinegar, lemon juice contains citric acid, which can effectively break down efflorescence. Squeeze fresh lemon juice onto the affected area and let it sit for a few minutes. Again, use a brush or cloth to scrub away the deposits gently.

What breaks down calcium deposits?

White vinegar is a natural solution that can be utilized to dissolve calcium buildup. Sitting overnight, you will be able to remove lime buildup from the drain while avoiding the harsh chemicals in traditional drain cleaners. Avoid putting any store-bought chemicals down the drain.

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