Varnishing Recommendations

Clay plaster mixtures are designed to be completely natural and vapor-permeable. However, this does not mean they cannot be used simply as decorative plasters to create beautifully designed walls and be varnished with a protective coating, just like any other plaster.

Will walls varnished with Mr. Clay Varnish No. 1 still be "breathable"?

– Certainly not. The purpose of the varnish is to completely seal and protect the surface from possible liquid or dirt absorption. Although this varnish is highly durable, it is safe to use and complies with all current regulations.

Mr. Clay Varnish No. 1 is an acrylic varnish made by the German manufacturer Einza, based on water.

We are very pleased with this varnish, as we had been looking for such a product for many years—one that:

- Is safe to use;

- Is easy to apply to walls;

- Is truly effective and resistant;

- Maintains a natural, matte finish;

- Minimally alters the wall color.

Can you varnish in shower or bathroom areas?

No. It is not allowed to use clay plaster and this varnish in showers, near bathtubs, or in any other areas with frequent water contact and high steam concentration.

In general bathroom areas (walls, ceilings, around freestanding bathtubs or sinks, where there's no standing water or intense steam): yes, it is allowed.

Can you varnish a kitchen backsplash?

We cannot guarantee 100% that it’s suitable :)

However, if you apply several coats of varnish, it is likely to work well. In practice, we’ve seen that even furniture-grade panels (designed for this purpose) don’t always retain their original look over time. So, weigh the pros and cons, and keep in mind that you can always refresh the surface by reapplying plaster over it.

Practical tip:

It’s best to varnish the backsplash area before the kitchen furniture is installed, making the varnished area larger than what will be visible. This ensures it will be well protected under the cabinets.

It’s also essential to seal all inner corners (between the countertop and wall) with sealant, so that standing water does not reach unvarnished areas.

Does varnishing change the color?

That depends on the color.

Bright and cool colors tend to become more intense and warmer, more than light and warm shades.

However, this change is often so subtle that it's not worth worrying about. Even if only some walls are varnished in a home, it’s usually difficult to notice the difference, as lighting varies across all surfaces.

Important: Always varnish from corner to corner.

If you know you'll be varnishing, we recommend ordering a color sample with varnish to preview the final result. You can order a sample [HERE].

We also provide comparison samples to show potential color differences between varnished and unvarnished walls.

How many coats of varnish are needed?

One coat is enough for dry, low-traffic areas. Apply two coats where there is greater risk of friction, stains, or splashes.

How to clean and maintain varnished walls

Regardless of how resistant the varnish is:

- Start by cleaning all stains with a soft sponge soaked in water or mild detergent.

- For stubborn dirt embedded in the plaster’s texture, use a soft-bristle brush.

- For colored or tough stains (e.g., markers, coffee), you can use a cotton pad with ACE bleach. This often removes such stains from both natural and varnished clay surfaces without visible marks.

Always test this method in a small area first.

Are there natural varnishes?

In theory, yes – natural varnishes exist on the market.

But based on our experience: they don’t work. Cleaning and maintenance remain the same as on uncoated walls, and the finish often changes the wall color significantly or applies unevenly.

So we believe it’s not worth spending money on ineffective wall protection.

It’s simpler and more cost-effective to learn how to care for and refresh natural clay plaster walls, which is very doable.

Is it necessary to varnish clay plaster walls?

Not at all – and we’re always happy when people consciously choose to keep a completely natural wall finish in their homes.

Clay plaster is a natural mixture without harmful chemicals, and it is fully vapor-permeable. This means cleaning it differs from materials that form a sealed film on the surface. Even though it’s natural, this does not mean it will wear out quickly — it depends on your lifestyle, habits, and maintenance.

We can sincerely say that such walls are delightful — they make you want to touch them, and the atmosphere at home feels very cozy.

Learn more about caring for and repairing natural clay plaster walls [HERE].

Clay plaster should be varnished when used in commercial or public spaces, where people may not realize it is a natural wall finish and therefore might not treat it carefully.
It is also strongly recommended to varnish any decorative objects or furniture finished with clay plaster.

Mr. Clay Varnish No. 1 – Application Instructions

Apply directly onto Mr. Clay clay mixtures.

For better resistance, apply two coats.

Apply the second coat only after the first one has dried completely, approx. 12 hours later.

Mix well before use.

Apply using even directional strokes.

We recommend using the Storch DuraStar 12 roller.

⚠️ Most Common Varnishing Mistakes

- Do not pre-outline corners (inner or outer) ahead of time. Doing so may cause visible overlaps or blotches when fresh varnish hits already absorbed varnish.

- Do not use any tools other than a roller.

Some use brushes or dab into hard-to-reach corners — this almost always leads to visible dark patches. Use a smaller roller for those areas instead.

- Protect adjacent walls in corners with Washi masking tape, so the roller doesn't touch neighboring surfaces. If you need to varnish both walls at once, insert a putty knife into the corner while rolling.

- Varnish evenly, expanding the area gradually with enough varnish on the roller.

First time varnishing?

Start with one or two walls, let them dry, evaluate the result, and only then continue.

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