Flagstones have been used for centuries as an aesthetic material for indoor and outdoor structures. But, the beauty of these stones is very difficult to maintain because of their excessive porosity nature.
As the stones are very porous, it destroys the look of the stones and reduces their longevity. Here comes the flagstone sealer to maintain their aesthetic look for a long time and protect them from any kind of moisture damage.
And in this guide, we bring you a list of the best flagstone sealer available after an incise research on them. Besides, you’ll get a detailed guide to easily find out which sealer can be more effective for you.
Which Types Of Sealers Do You Use On Flagstone To Seal Well?
The types of sealers you want to use on flagstones depend on many factors like the finishes of the stone, the location where you want to use the stones, the purposes of using the sealer, etc.
Considering all these factors, we have selected some sealer types that can be used in flagstones to seal them well.
a) Silane Siloxane Sealer:
Silane Siloxane sealers are the types of water repellent penetrating or impregnator sealers. They are considered one of the best sealers that can be used on flagstones. As they are water repellent sealers, they build up a hydrophobic barrier within the flagstone’s pores.
By doing so, they make the stones resistant to water as well as stains. Besides, these sealers also protect them from the growth of mold and mildew, salt damage, UV rays exposures, etc. If you want to give the flagstones a natural stone finish and want to protect them for a longer time, you should go for this type of sealer.
It doesn’t matter whether they are used for indoor or outdoor surface application; these sealers perform the best.
b) Natural Stone Sealer:
Most natural stones possess high porosity, and flagstones are one of them. Due to this nature, they permit water, oil, and various contaminants to sit on them that cause serious defects of the stones. So, to repel the flagstones’ damage by providing a protective natural look, a natural stone sealer does a great job.
These types of sealers are being used on flagstones to seal them well on indoor and outdoor structures (floor, patio, courtyards, etc.). They are the best sealer for providing a natural stone matte finish.
c) Acrylic Concrete Sealer:
Acrylic concrete sealers are moisture-sensitive sealers and also are not breathable. Due to this reason, they are usually used on concrete. But, they are also being used on flagstones for providing a wet look and high gloss finish on them.
So, to enhance the aesthetic natural color and texture of your indoor structures’ flagstones, these acrylic concrete sealers are a great choice. Besides, they will also protect the stones by offering a tough and highly protective finish.
However, you should use this sealer on your flagstones before verifying its compatibility to sit on the stones.
d) Water & Solvent-based sealers:
Both water and solvent-based sealers are the types of penetrating or impregnator stone sealers. Therefore, they protect the flagstones from any water and stain damage.
Besides, they also deliver a longer performance. These sealers prevent moisture and stain substances by blocking the stone pores. However, although both are penetrating sealers, water-based sealers prevent the flagstones moisture better than solvent-based sealers. This is because the water-based sealers permit the stone to breathe even after blocking the pores. On the other hand, a solvent-based sealer protects the flagstones better from any type of oil contaminants, grease, etc.
Water-based stone sealers are used for indoor and also outdoor surface applications. Solvent-based sealers suit less while being used on the indoor application due to having VOCs that produce toxic fumes and unpleasant odors.
9 Best Flagstone Sealer Reviews of 2021:
1. Siloxa-Tek 8500 Penetrating Concrete Sealer:
Siloxa-Tek 8500 is another top-notch water repellent sealer that comes with an industrial-grade. With its exclusive water repellency feature, it protects the stone surface from moisture intrusion.
So, if you want to protect your stone surface from all types of harmful material that is water-soluble, this sealer is a great option for you. Not only that but also it prevents salt as well chloride damage, cracking, pitting, and spalling of the stone surface, and also freeze-thaw cycles. Therefore, there is nothing to worry about your concrete and also masonry substrates.
Besides, it comes with new high-performing nanotechnology, one of the most amazing features of this sealant. With the intelligent nanoparticles, it penetrates deeper into the stone surface.
Thus, this sealer provides outstanding water beading effects and deeper water penetration. And, also adds an extra layer on the surface for protection. This nanotechnology also helps to form an invisible hydrophobic barrier on the concrete surface. Thus, when the sealer gets dried on the surface, it provides a clear and natural appearance.
The Siloxa-Tek 8500 sealer contains low VOCs and also has low odors. It is a 100% breathable sealer, which means it permits water within the surface. And, also it helps to escape that water without any types of adverse effect on the sealer. As this sealer is an excellent chloride and water ingression reducer, so you can use this sealant on your basements, garages, driveways, pool decks, patios, etc.
Besides, it is very easy to apply. You can easily use this sealer with a sprayer, brush, as well as roller. One gallon of this Siloxa-Tek 8500 sealer can cover up to 250 square feet per coat.
Excellent protection from moisture infiltration.
It doesn’t leave any surface film.
Increases the durability of the stone surfaces.
Doesn’t change the surface color and keeps its natural look.
It comes with easy maintenance.
Expensive sealer product with a low amount of sealant.
The thickness of this sealant is relatively low.
The Siloxa-Tek 8500 is an excellent water and salt repellent concrete sealer to use indoors and outdoors. Besides, as it’s ready-to-use sealant products, this is the best sealer for beginners.
2. Armor WL550 Matte Wet Look Sealer:
We will wrap-up our reviews with this Armor WL550 stone sealer. It is a penetrating water repellent sealer for unsealed concrete, brick, pavers, flagstones, slate, and porous masonry.
So, if you want to prevent your pavers from getting into a slippery surface, the Armor WL550 is the perfect sealant that meets your requirements. Due to having the water repellent nature, it helps to repel the water and also reduces the damage and deterioration.
Besides, it protects the surface invisibly by offering it a wet look. This sealer provides this wet look by forming a hydrophobic barrier that absorbs water up to 95% with chemical reactions. It also won’t leave any surface film once the sealer dries on the surface. While you finish your sealing project, you will experience darkening the stone surface to enhance its color.
Yet, this sealer is breathable and also UV stable like all other wet look sealers. Therefore, you don’t have to maintain the stone surface coating with this sealer.
And it is also a long-lasting sealer. With just a single coat application of the sealant, it lasts for up to 3-5 years. So, there is no need to reseal the stone surface within this time.
Creates a hydrophobic barrier within the pores.
Brings out the color for dull and faded surfaces.
Protects from cracking, spalling, and pitting of the surface.
Resistant to UV rays and also to the growth of mold and mildew.
Has a strong solvent smell.
Overall, the Armor WL550 Matte is a great sealant product for outdoor application on the flagstone. This can also be used on indoor surfaces, but due to having its strong solvent odor, you can avoid it for your interior application.
Therefore, it is a great sealant for professionals. And, although the application is quite easy, you need to be more cautious while applying the sealer with an HVLP pump sprayer if you are a beginner.
3. SX5000 WB DOT Approved Water Based Silane Siloxane Penetrating Concrete Sealer:
Our next pick is the SX5000 Penetrating Concrete Sealer; a water-based and Silane Siloxane type of sealer that contains high solids.
It is another one of the best concrete sealers that you can use on both unsealed indoors and outdoors, the concrete surfaces vertically and horizontally placed, and various natural stones like flagstones, slate, brick, and pavers. It lets you provide a breathable sealer having low VOCs. So, this sealant is easy to maintain on the surface. No recycled or imported resins are used in the formulation of this sealer.
Besides, it has the approval of the Department of Transportation Institution, so this sealer can be used on roadways and bridge decks. It not only reduces moisture damage but also protects the surface from deterioration. It also preserves the natural as well as the unsealed appearance of the substrate.
And, the most amazing thing is that this sealant doesn’t create a slippery surface film. It will never alter the stone color and frees you from the worry of getting a stone color change.
It contains the ingredients that are more active up to 10X to protect the concrete surface.
Permits the substrate to breathe properly.
Doesn’t trap the moisture below the concrete surface.
Easy to use.
Produces some white discoloration on the bricks.
Needs to quickly seal the stone surface.
This SX5000 is a high-quality water-based sealant designed to use on interior or exterior unsealed surfaces such as pool, patio, roadways, sidewalk ways, etc.
No matter if you are an amateur or an expert, you can easily apply this sealer on your unsealed surfaces.
4. Armor AR350 Wet Look Concrete Sealer and Paver Sealer:
Here’s another Acrylic-based sealer, and that is Armor AR350 Concrete Sealer. It is a kind of high solid acrylic coat penetrating sealer that comes with superior performance.
This sealer is super durable and also lasts for a long time on the surfaces. It is a professional-grade solvent-based acrylic sealant that offers a satin sheen wet look finish on the stone. It works best for bringing out the lost color in dulled substrates. Also, it seals better both the indoor and outdoor poured concrete, stamped concrete, and concrete paver surfaces.
Not only that but also it enhances the color and provides excellent protection of those concrete and pavers. It protects the stone from water, stains, salt damage, chemical damage, and harmful UV rays.
Furthermore, this sealant is also a non-yellowing and breathable sealer. Thus, it creates a dark wet look with a low to no gloss finish and preserves the stone’s natural color.
Yet, one gallon of this sealant can cover up to 100 square feet in two coats. If the sealer is appropriately applied on the surface, it can last up to 2-5 years.
Natural coloring with a transparent low sheen finish.
It needs low maintenance due to its self-priming nature.
Reduces dusting and deterioration of the concrete surfaces.
It contains low volatile compounds.
Superior adhesion to the concrete and paver surfaces.
It produces an overwhelming smell as it’s a chemical sealant.
Needs to wear appropriate PPE while using the sealer.
The Armor AR350 sealer is intended to use on usually concrete and paver surfaces to give them a low gloss finish. And, also this sealer is not recommended to use on any type of natural stone.
It is an excellent choice for the experts. However, if you are a beginner, take extra precautions and use anti-slip powder while using it.
The EnduraSeal concrete sealer is considered the best acrylic solvent sealer. This is because; it offers an acrylic component that is 100% pure.
So, if you are looking for a high-performing acrylic solvent sealer that offers low odor, the Endura Seal is the best option for you.
This sealant performs best while producing a semi-gloss, low shine, and wet look finish on the stone surface. The sealer coating is highly durable to protect concrete, pavers, terrazzo, stones, etc.
In addition to providing other features, it also comes with a non-yellowing feature. Thus, you can enhance the beauty of all kinds of the concrete surface by using this sealer. It doesn’t matter if they are stained or colored or stamped or exposed aggregate.
This highly durable sealer works better than any type of Urethane and Epoxy sealers. So, it doesn’t provide an overly glossy finish on the stone. This sealer gives the best result while it is applied on two thin coats on the stone surface.
About one gallon of the Endura Seal Concrete sealer can cover up to approximately 150-300 square feet. Yet this coverage rate depends on the stone surface porosity.
It maintains the glossy appearance of the stones.
Doesn’t get the stone surface yellow over time.
It suits best on stained surfaces.
Creates a huge mess and massive bubbling if inappropriately used.
Became cloudy after a few months.
It offers a very appreciable semi-gloss finish with enough coverage of the surfaces that will surely satisfy you.
Yet, this sealant is best for professionals to use than beginners. This is because it has to be used correctly; otherwise, the result will be horrible.
6. DOMINATOR Stone Sealer and Clay Brick Sealer:
Nothing can beat this DOMINATOR Stone Sealer when it comes to providing a wet look and a low gloss finish to the outdoor stone.
Not only that, but also this sealer keeps the stone surface clean for delivering a natural appearance. This sealer is used on clay pavers, faux stones, travertine, etc. But, one thing you need to remember that this sealer can’t be used on surfaces that are submerged.
It also increases the longevity of the stones. This is a kind of film-forming sealer that acts as a safeguard to prevent moisture and spills. The DOMINATOR stone sealer is breathable. Due to having low volatile compounds on the sealer, it doesn’t produce any foul odor.
Besides, this sealer maintains the outdoor surface with high performance. It has an industrial-grade UV additive. Therefore, the sealant is resistant to UV and harmful rays of the sun. This clay brick sealer is also a color-enhancing sealer that offers a low gloss to no gloss finish. It offers the stone surface long-lasting protection.
A professional contractor who requires an excellent sealant product for his exterior surfaces should go for this incredible stone sealant. One gallon of this sealant can cover up to 1,000 square feet.
Provides natural-looking no sheen finish.
Enhances the look of the stone.
Protects the porous stone from Arizona sun and heavy rain.
Easy to spread and enough sealant to cover the area.
Easy to apply.
It leaves a few tacky areas if the sealant is applied at a heavy rate.
Produces milky white film when wet.
It is a perfect choice for the beginner level and the professionals as it’s super easy to install on your stone surface. Besides, the price-area ratio and the total coverage rate of this sealer are also impressive.
This Masonry Defender Penetrating stone sealer comes with a non-glossy invisible coat finish to protect the concrete surfaces. It provides clear protection that will never leave any residual appearance on your stone surfaces. So, this sealer can be used on the concrete driveway, sidewalk, or patio, etc. It is also a masonry water proofer. Therefore, it makes the stone durable that lasts for up to 5 years.
The Masonry defender sealer is a water-based penetrating water repellent sealer that provides long-lasting water protection. It is also breathable, causing the water to bead.
All of these features make it a powerful concrete sealer. If you want to keep the newer look of your concrete driveway and protect it from any cracking or pitting stone damage, this sealer works the best. It also protects the surface from salt damage, chlorine damage, freeze-thaw damage, effects of efflorescence stain substances, etc. So, using this sealant on the pool flagstone perfectly protects the stone surfaces.
Furthermore, this sealer also offers a 3-year of limited warranty to use on horizontal concrete surfaces. So, buying the sealant for your concrete surfaces must be a great decision for you.
Water repellency for a long time.
It doesn’t alter the surface appearance and maintains the original color.
Easy to apply.
Odorless and fast-drying sealer.
It comes at an affordable price.
Creates a blotchy mess on the stone surfaces.
Sometimes, it can leave fewer dark spots.
This Masonry Defender is perfect for concrete surfaces, concrete driveways, sidewalks, patio, etc. Its non-filming nature makes it extremely practical to use on outdoor surfaces.
8. Rain Guard-CR-0356 Silane Siloxane Water Repellent Sealer:
Rain Guard-CR-0356 is a silane siloxane water-based concrete sealer intended to create a hydrophobic barrier on the flagstone surfaces.
This micro-seal clear spray sealant is used on any type of masonry, horizontal or vertical surface. It can restore and preserve the stone performance.
Thus, this sealer protects the surface for many years to come and extends the stone life by making it long-lasting.
As it’s a clear sealer, it won’t change the surface’s normal appearance. Besides, this sealer also doesn’t produce any surface film on the stones. It comes with a non-yellowing formula and no-sheen as well.
You can use this Rain guard sealer as a primer before painting. This is because; it can repel moisture out from the surface. It can easily protect the stone from stain substances such as oil, gas, anti-freeze, etc.
This sealer is a 100% penetrating water repellent sealer. Therefore, it is most likely weather resistant.
It prevents weathering the stone, moisture damage, salt damage, snow damage, and wind-driven rain. It is also UV resistant and protects the stones from excessive harmful sunlight exposure.
With this sealer product, you will get a 10-year satisfaction warranty. Due to its weather-resistant nature, you can use the sealer anywhere in the country you wanted to use.
It comes with ready to use formula.
It performs best on porous stone surfaces.
Newer appearances to the treated surfaces.
Easy clean up with soap and water.
Fast-drying sealant product.
The consistency of the sealer product is poor.
It tends to run off while applied on sloped surfaces.
Rain Guard-CR-0356 works great with most porous stones by protecting them against moisture, stains, and also slippage when it rains.
So, it’s best suited to use on outdoor flagstone surfaces. And, as it’s a ready-to-use sealant product, this is the perfect sealer if you are a beginner.
9. Glaze ‘N Seal Clear Extra Strength Penetrating Sealer:
Glaze’ N Seal Penetrating Sealer is a high-quality sealant for stone care, offering an extra-strength formula that makes the flagstone more durable.
So, while using concrete and masonry surfaces, this sealant protects the stone from the water, any kinds of dirt and debris, stains, and the buildup of mold and mildew.
This Glaze’ N Seal is a strong, low-gloss, super-fast drying water-based sealer product. Thus, it creates a water repellent barrier on the stone surfaces within 24 hours.
It also protects the stone from oil and grease without producing any harmful vapor. That makes it a safe sealer product. The most striking part of this sealant is that it provides a natural look of the stones. And, this natural look lasts 8 years or more.
So, you can use this sealer on your pool, patio, and floor without any hesitations as it perfectly preserves natural appearances. This sealer product doesn’t contain any harsh solvents. So it’s quietly safe for all types of natural stones. These stones include flagstones, marbles, limestone, quarry tile, concrete tile, granite, slate, brick, porcelain, terra cotta, masonry, etc.
It is also a slip retardant. So, when wet, this sealer helps to protect from being the surface slick and slippery.
Ensures maximum penetration.
Offers invisible protection of the stone.
Beautifies the flagstone appearance without changing color or surface texture.
Easy to apply.
Over-saturating this sealer will leave a white residue.
Doesn’t seal stones from stain substances.
Even if you are not an expert, you won’t find any problems in sealing the flagstone, whether you use it indoors or outdoors. This sealer is so easy to use not only for a professional but also for beginners.
How to Seal Flagstone Outdoor & Indoor:
To prevent the flagstone from spalling, cracking out, flanking, etc., outdoor and indoor flagstone should be sealed with the proper sealers in an appropriate procedure.
Here, we have discussed the process, in brief, to seal flagstone outdoor and indoor around the pool and patio and floor, etc.
Sealing of Flagstone Outdoor (Around Pool & Patio & Floor):
To seal flagstone outdoor, you need to follow the given process step by step-
Step 1. Place The Flagstone According To The Correct Size:
To seal the outdoor flagstone structures like around the pool or patio or floor, the first step is to place the flagstone on the surface by cutting them into the proper size with a chisel and hammer.
Step 2. Fill Up The Cracks With Filler Material:
After that, fill the small cracks with self-leveling sand sealer filler material. This step is more useful for sealing the patio and floor.
Step 3. Clean of The Stone Surface:
The next step is to clean the surface with cleaner and, if possible, power washed the place for sealing the pool and patio as well. And allow the flagstone surface to dry for at least 24 hours or more.
Step 4. Seal The Flagstone With The Sealer:
After cleaning and drying the surface, the final step is to seal the flagstone with the proper flagstone sealer.
Here, in this step, if you want to seal the pool, you should use the types of flagstone and the sealer that can protect it from salt and chlorine damage. And in the case of the patio and the floor, you should use a penetrating or impregnator sealer to protect it from moisture damage.
Use the sealer on the surface by roller brush or sealer sprayer. You should first apply one coat of sealant for penetrating sealer and wait for drying the surface and then apply the second coat if the stone permits.
Step 5. Dry The Sealer On The Stone Surface:
When finished with the last coat, let it dry overnight and at least 72 hours before the surface is exposed to the moisture. This sealer cures within 10-14 days after the final coat.
Sealing Flagstone Indoor (Around The Floor):
To seal flagstone indoor, follow this guideline also according to the step-
Step 1. Clean And Dry The Stone Surface:
The sealing procedure of indoor flagstone structures is more likely the same as sealing flagstone outdoors. To seal the indoor flagstone, first, the surface should be cleaned nicely and also completely dry.
Step 2. Pre-Seal The Surface:
After that, if pre-seal is required, apply the sealer for 1 to 2 coats on the stone surface.
Step 3. Seal The Stone With Sealer & Dry:
For indoor flagstone, apply film forming type sealer for 2 to more thin, even coats. Then, let the sealant dry for at least 1-3 hours in between the coats.
Step 4. Polish The Surface:
For indoor flagstone around the floor, polish the surface with a high gloss or matte finish and let it dry for 60 minutes between the sealer’s coats.
Question: What is the best flagstone sealer wet look?
Answer: Generally, a modified silicone or acrylic-based sealers are the best sealers for a flagstone wet look.
They are also a color enhancer of the flagstone and wet look sealer. This type of sealer is usually used to beautify the flagstone outside the structure.
These sealers are highly vapored permeable and provide a high gloss wet look finish on the slip retardant stone. They also protect the flagstone from UV rays as they are resistant to harmful sunlight exposure.
Question: Why Do I Need to Seal My Stone? What are the pros and cons of sealing flagstone?
Answer: Sealing of the flagstones is necessary as they are porous. For this reason, the stones allow the moisture to absorb, which causes damage to them like cracking and scratching of the stone, seeping of staining substances, allowing infiltrations of oil, water, and dirt, etc.
And, ultimately, it makes the stone less durable. So, to protect the flagstone from damage and make it durable and preserve the beauty of the stone, you need to seal your stone.
Pros of sealing flagstone:
It helps to block the pores by filling them.
Repels water from the stone.
Extends the longevity of the stones.
Makes it weather resistant.
Prevents the formation of mold and mildew growth on the stone surface.
Cons of sealing flagstone:
It makes the stone surface slick and slippery when wet.
Causes breakdown of the porous flagstone if the sealers are not being appropriately applied.
Question: How to repair flaking flagstone?
Answer: To repair the flaking flagstone, you have to follow the given ways-
First, you need to remove all the tiniest loose materials like dust and stones and the lingering particles from the stone surface.
After removing loose stuff, the next step is to clean the surface of the flaking flagstones with an approved cleaner to clean off the dirt and debris.
Then, you have to apply a sealant when the surface is cleaned and completely dry off. Besides, you should also use the flagstone made from tough and hard stones to avoid flaking of these stones.
Question: How often should you seal flagstone?
Answer: How often you should seal your flagstone depends on the stone finish and the excellence of the stone. However, you are recommended to seal flagstone every three to four years to remain the stones like new.
Ensuring the flagstone’s beauty with all types of finish like wet look, natural stone color, matte finish, high or low gloss finish is possible by sealing them with the best flagstone sealers.
They let your stone provide a high-quality finish and make the stone highly durable and long-lasting. However, you will get all the sealer benefits if you use the best sealant products on your flagstone surfaces.
Yet, you should keep in mind that there are some limitations to using the best stone sealers as well. So, when you select the sealer, you should know in detail about them.
And, of course, don’t choose cheap sealers. It will help you to get better sealers and protect the stones from all sealer problems.
Hi, I am Rogers Weber, the man behind Solvesonic. I am a mechanical engineer. I use many kinds of tools almost every day at my workplace. I love to write about tools, home improvement, and DIYs. I enjoy helping people to solve their problems through my website.