How To Seal Slate Countertops

How To Seal Slate Countertops
  • Author: Amanda Arnold
  • Posted On: February 10, 2022
  • Updated On: August 21, 2023

Slate is a stunning material for a countertop. It has a lovely stone feel and a wonderful range of light to dark grey shades, with the possibility of deep rich colors.

Slate countertops are a hard surface that is rarely used in kitchens. This is extremely metamorphic, meaning it will alter over time and improve in appearance as long as it is properly cared for.

Slate countertops necessitate meticulous upkeep, which you should accomplish by following the guidelines below. Slate is a permeable stone with a lovely appearance in the kitchen and bath.

However, if it is not cleaned properly, the surface may etch. So, knowing how to clean slate countertops is essential if you want to keep their beauty for years to come.

Why Do You Need To Seal The Slate?

Slate is a natural stone that is commonly used for countertops and flooring. Slate is a metamorphic rock composed of stratified bands of dark minerals. During tectonic mountain-building processes, the mudstone sediment on which slate forms is baked by intense heat and pressure, resulting in these layers.

Slate does not require sealing in general, but if used as roofing material or on a high-traffic surface, it will most certainly benefit from a sealant. The slate will be protected from weathering and stains using a suitable sealer.

It’s especially crucial to seal slate if you’re using it in a damp area like a bathroom or kitchen. Slate countertops can become damaged and pitted over time due to moisture in the air. This type of damage can be avoided using a suitable sealer.

Know The Type Of Sealer Before Sealing The Slate

Generally, there are two types of slate sealers, including penetrating and topical sealers. A penetrating sealer penetrates the stone, whereas a topical sealer sits on top like paint. While both can conceal stains or add color, only penetrating ones offer protection against build-ups and stubborn stains.

Some people combine the two for optimal effect, using a penetrative sealer first, then polishing the surface to make it bright and protect it from wear and tear over time. Using a penetrating sealer is usually sufficient.

Steps To Seal Slate Countertop

No doubt, you can seal the slate countertops yourself without any professional assistance and hiring. You can also follow the below steps to seal the slate appropriately:

1) Clean Out Debris

Remove any dirt or dust on the slate countertop using a wet cloth. This step is crucial because you don’t want to put a sealer over anything filthy. Make sure to dry out the towel before wiping it on the counter to avoid a major mess and soapy water all over the place.

Wipe down your slate countertop with the non-abrasive towel that has absorbed the soapy water. Rinse the towel regularly in the bucket to eliminate any dirt it has picked up.

2) Use A Mild Cleaning Mixture

In a spray bottle, combine equal parts white vinegar and water. Allow the mixture to settle for a few minutes after spraying it onto the slate. You can also use a commercial slate or natural stone cleaner if you have one. Wipe the slate clean with a gentle cloth and allow it to dry completely before applying any sealant.

If debris or residue remains on the surface, reapply the vinegar and water combination as directed above. Allowing the slates to remain in direct sunshine for an hour has also been found to help remove stubborn dirt.

3) Dry The Countertop After Cleaning

Using a dry microfiber cloth, gently dry the stone once more. Ensure that the water on the countertop has been completely cleared. Every time you wipe off your countertop with water, it’s a good idea to dry it. This should keep any blemishes or mineral deposits at bay.

4) Add Sealer

It’s time to seal the slate now that it’s clean! Choose from various slate sealer brands to choose the one that best suits your needs. Using a brush or roller, apply a coat of sealant to the slate’s surface. Make sure to use even strokes and avoid puddles while applying sealant.

Allow for complete drying before applying the second layer of sealant. Make sure to follow the manufacturer’s instructions to the letter.

5) Let The Sealer Dry Completely

Allow for thorough drying of the sealant before using the countertop surface. A sealer usually takes a full day to dry completely. Reseal your slate countertops after every one or two years for best results.


To protect your slate surfaces from harm, seal them as soon as possible following installation. Use a stone cleaner and a small amount of water to clean the counters. To dry the surface, use an old towel. Apply a sealer to the surface and spread it evenly with a clean towel.

On your slate countertop, use caution while handling cookware. The impact of large goods being dropped against the countertop might cause the slate to break and crack.

It helps if you take precautions to protect your countertop from scratches. Food should not be cut immediately on the counter. To avoid damaging the sealed countertop, make sure to use a cutting board for fruits and vegetables.

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Author: Amanda Arnold

Amanda has been working with ConstructionHow since 2021. Her experience spans over 5 years in the creative niche such as home decor and trends, landscaping, renovations, and custom architectural values. As a home designer expert, she has a keen eye for the latest home improvement trends with accurate facts that readers find impossible to ignore. Being invested in home-building trends is how she has gained her lucrative expertise exploring more to bring a positive ambiance for all homeowners (and even tenants!). Currently, she lives in a beautiful beach home, a source of fascination for her.