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Silane Siloxane Sealer – CoverSeal Pen50 Water, Salt, Mold and Mildew Resistant Coating


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Location : Interior/Exterior
Task : Water Repellent, Salt, Mold Resistance
Application : Sprayer or Roller
Surface : Concrete, Stucco, Stone
Base : Water Based
Drytime : 30-45 Min.
Coverage : 260ft² per gallon
Finish : Clear

CoverSeal Pen50 Natural Look, Water-Based Penetrating Silane Siloxane Sealer

Prevents Cracking & Spalling. Mold And Mildew Resistant. Blocks Salt Damage From Chlorides.

CoverSeal Pen50 Product video

CoverSeal Pen50 Un-boxing video

What Is CoverSeal Pen50 Water, Salt And Mold Resistant Penetrating Sealer?

CoverSeal Pen 50 sealer is a penetrating silane siloxane sealer . This means that it penetrates into the surface – concrete, stone, terrazzo etc. – without leaving a film on the surface.

It’s very water resistant. It’s made from a blend of silanes and siloxanes that penetrate into the concrete. These substances react to form a silicone resin that’s highly water resistant and highly repellent.

It does an excellent job of keeping water out of the concrete or stone, and it will protect it from mold growing. It will protect it from salts getting into the surface from freeze-thaw attack.

You can use it in both interior and exterior applications, and it will protect your concrete or other porous surfaces.


  • Long term protective repellent layer
  • Prevents Cracking and Spalling
  • Water-resistant
  • Excellent penetration into porous substrates
  • Mold and mildew resistance
  • Blocks salt damage – chlorides
  • Breathable
  • Reduces water absorption
  • Reduces dirt pick up and staining
  • Retards efflorescence
  • Zero odor (low VOC)
  • Easy to apply

Typical Uses

  • Architectural Concrete
  • Concrete Block
  • Splitface Block
  • Roofs Tiles
  • Porous and Dense Brick
  • Stucco
  • Exposed  aggregate concrete
  • Stone and Slate Tile
  • Pavers

Shelf Life

18 months when stored at 77°F (25°C) or less in a dry and shaded area.

Theoretical Coverage

260ft² per gallon (6.5m²/L) per coat.

Very porous substrates will require a two coat application or higher application rate.

Typical Situations Where Someone Would Use CoverSeal Pen50.

Much of the time, our customers using Pen50 are dealing with exterior situations.  Typically, they come to us describing situations where moisture got into surfaces, resulting in mold and mildew.   When this is the case, we usually recommend Coverseal Pen50.

Other typical examples of where a penetrating sealer would be useful include natural stone like limestone or sandstone that is:

  • – In your patio
  • – Around your pool deck
  • – On brick walls
  • – On vertical surfaces like outdoor showers or artificial waterfalls.

Anywhere it can get damp, and you need to prevent that moisture getting into the surface, that would be an ideal application for Coverseal Pen50.  And again, most customers love that they can use it, without it changing the appearance of their surfaces.  It does not darken the surface. It won’t give it a sheen. It’ll just keep that natural look.

Another reason customers love Coverseal Pen50 is that it protects surfaces from what we call “freeze-thaw” attackPen50 easily repels that moisture from getting into the surface, and causing the crumbling and cracking of the surface.

Examples of exterior applications include:

  • – Driveways
  • – Patios
  • – Pool decks
  • – Etc.

Commercial applications include:

  • – Building entrance ways
  • – Public walkways
  • – The walls in warehouses and buildings
  • – Etc.

All of these surfaces need strong protection those from freeze-thaw attack.

Last of all, your surfaces need protection from chlorides.

If you’re using de-icing salts during the winter, they can be carried into the surface via the melting ice or snow.  CoverSeal Pen50 would provides a highly durable barrier against the moisture and anything in it.  It would repel those chloride chemicals from getting into your concrete or natural stone.

When Applying CoverSeal Pen50 To A Surface, What Are The Recommended Steps?

Using Pen50 is very easy.  It’s a water based product.  It’s not hazardous. However, the first step is making sure the surface is porous or absorbent.  Basically, the sealer must be able to soak into the surface rather than just sit on top of it.  You can test this by putting some water on the surface, and making sure it is fully absorbed.

You will need to clean off anything that may prevent the sealer from being absorbed into the surface pores.  Things like dirt, oils or debris will need to be removed as best as possible.  Obviously, if there is any mold or mildew present, you should clean that off before applying the product. Assuming that the surface is clean and passes the water-absorption test, the next step is to apply the product using a pump-up sprayer.  That’s probably the most effective way of doing it.

Spray the product over the surface as evenly as possible. It should soak into the pores within 5 to 10 minutes.  If it hasn’t soaked in by that time, spread the product laying on the surface around or sweep it off into an area that hasn’t been sealed yet.

When it comes to coverage area, you’ll get around 150 to 250 square feet per gallon, depending on the porosity of your surfaceIf your surface is very porous, it can take 2 coats.  Depending on the ambient temperature while applying the product, apply the 2nd coat at least 1 hour after the 1st coat.  If your surface is not very porous, you’ll notice the product will be slow to soak in.  In these cases, 1 coat should be sufficient.

We always recommend that you wait 4 hours before exposing it to any moisture or water.   After that, you’ll find it can be driven on or walked on, and be exposed to moisture.  You will be able to walk on the sealed surface within 1 to 2 hours, depending on the temperature.  The longer you let the Pen50 sealer be absorbed into the surface pores, the more effective it will be.

In the background, the surface is going to continue to cure for the next 24 hours. As a result, you’ll experience maximum water-repellence after 24 hours.

CoverSeal Pen50 Case Study:

Here’s what Bob – a user of CoverSeal Pen50 penetrating concrete sealer – had to say about it after applying it to a basement area for a customer of his.

Is A Silane Siloxane Sealer The Right Concrete Sealer Product for Your Situation?

Ah, the great outdoors – we have all been, enjoyed and cherished the experience of being exposed to the sun, wind, rain, snow and all the other elements which comprise the great outdoors. It’s really no wonder why people choose to live in homes which provide that all-encompassing sense of protection and comfort.

Unfortunately, over time, home exteriors can experience damage due to the effects of moisture, water and other environmental issues. The result is exterior surfaces which become increasingly vulnerable to further damage, resulting in cracked and peeling paint, rotting wood and other more serious issues.

The good news is that there is a great way to protect your home and its exterior with Silane-Siloxane Sealer, which is both effective and long-lasting when it comes to safeguarding the outward appearance of your home. In this comprehensive guide, we will cover everything from what you need to know about Silane-Siloxane Sealer, to the benefits of this product, to the best practices for its application.

We will even look at some FAQs so you can get the most out of your Silane-Siloxane Sealer! So, let’s get started!

Quick Clarification

Silane-Siloxane sealers are protective water-repelling sealants used to protect concrete and masonry surfaces from water damage, staining, and the freeze/thaw cycle. These sealers can help to keep surfaces clean, prevent mold and mildew growth, and extend their lifespan.

What is a Silane-Siloxane Sealer?

A Silane-Siloxane sealer is a 1 part product part made up of a blend on silane and siloxane polymers. This product applied to concrete and masonry surfaces that helps protect them from water and UV damage. The Siloxane occupies the pores of the concrete and forms a highly repellent layer. The Silane molecules penetrate deeper into the substrate, providing additional protection for longer-term resistance to weathering. These products offer superior water resistance compared to traditional sealers, making them ideal for extending the life span of exterior surfaces such as driveways, walkways, sidewalks, and exterior walls.

One argument in favor of silicon-siloxane sealer is that it provides waterproofing, which can help prevent surface discoloration, salt intrusion, freeze/thaw attack and subsequent spalling and pitting due to the presence of water in the substrate. This can be especially beneficial if you have a concrete patio or driveway that is vulnerable to spotting due to rainwater running off surfaces around your home.

The sealer also reduces cracking by repelling water and moisture entering the surface and freezing during the winter. In addition, silane siloxane sealers are more durable than some other types of products and can provide years of protection when applied correctly.

On the contrary, some argue that silane-siloxane sealer may cause discoloration of the concrete surface if not applied properly. Applying too much of the product can also create a slippery surface that can be hazardous when wet. Whilst silane-siloxane sealers provide excellent water resistance they do not resist oil based continents like motor oil or food based oil and grease. Fluoropolymers are recommended , if you want to protect against chemical attack from oils, fuels, paints, and other hazardous materials.

In addition to protecting homes from the elements, silane-siloxane line the pores and crevices with an invisible film. Therefore they should not be relied upon to provide some aesthetic benefits. Topical sealers however will make porous surfaces look more even. They add a subtle sheen to the surface while still preserving its natural texture and color. Furthermore, the impermeable nature of a topical sealer provides a more absolute barrier to stains and oil contamination.

Ultimately, it’s important to consider both sides of the argument when deciding if silane siloxane sealers are the best option for your needs. After weighing pros and cons carefully, you can make an informed decision on whether or not Silane-Siloxane Sealer is right for your home’s outdoor surfaces. In the next section we will explore further what are the benefits of using silane siloxane sealer for protecting your home’s outdoor surfaces.

Top Points to Remember

Silane-Siloxane Sealer is a one-part product applied to concrete and masonry surfaces that helps protect them from water and UV damage.  It provides better waterproofing than traditional sealers, helping prevent discoloration and cracking, and is more durable. However, it can cause discoloration if not applied properly, is slippery when wet,. Whilst silane-siloxane sealers provide excellent water resistance they do not resist oil based continents like motor oil or food based oil and grease.

Ultimately, one must weigh the pros and cons before deciding if this type of product is right for their needs.

What Are the Benefits Of Using A Silane Siloxane Sealer?

Silane-siloxane sealers offer a variety of advantages over traditional concrete and masonry protection. The primary benefit of silane-siloxane sealers is their ability to penetrate deep into the surface, creating a moisture barrier that prevents water from entering and forming on the exterior of your home. This can prevent damage caused by standing water or humid climates, such as moss and mold growth, which can further erode concrete and stonework. Additionally, silane-siloxane sealers protect against chemical attack from deicing salts, chlorides, and other corrosive materials.

Silane-siloxane sealers have been proven to increase durability of masonry and concrete structures, both newly erected and aged alike. Studies show that sealing concrete and masonry surfaces with silane-siloxanes significantly prolongs the life span of such surfaces compared to those that are left unprotected. Additionally, these sealants act as an effective guard against internal weathering due to freeze/thaw cycles or other extreme conditions.

Perhaps the greatest benefit that comes with using silane-siloxanes is its cost effectiveness. Regularly applying these sealants requires only minimal maintenance on your part, and their low application costs ensure great value for money when compared to other expensive treatments.

These benefits make it clear why silane-siloxanes continue to be popular options for homeowners who wish to protect their property from corrosion or damage caused by weathering or hazardous chemicals. To further elaborate on how this type of sealer can enhance structural durability, let’s take a closer look at how they improve masonry and concrete structures in the next section: “Increased Durability of Masonry & Concrete Structures”.

Increased Durability of Masonry & Concrete Structures

Masonry and concrete structures are known for their long-term durability and strength. The application of a silane-siloxane sealer can help to increase this durability even further, ensuring that whatever structure you’re protecting lasts for decades.

The sealer penetrates below the surface level of the masonry or concrete to provide a barrier that repels moisture and blocks the penetration of harmful substances like chlorides, thereby preventing damage from any water-soluble salts caused by deicing agents or acid rain.

Blocking moisture penetration significantly reduces mold and mildew growth and because of the high repellency characteristics of silane-siloxane sealers the surface becomes much easier to clean and keep clean.

The use of silane-siloxane sealers can also reduce the chances of efflorescence, a type of staining caused by Calcium Carbonate deposits rising to the surface level. Applying the sealer helps form a barrier that prevents this staining and keeps the finish looking new.

Silane-siloxane sealers have been proven to protect against freeze-thaw cycles, reducing cracks in masonry and concrete walls, as well as having the effect of reducing water penetration through the surface. This protection means that your masonry or concrete walls are less liable to become spalled (deteriorated) in cold weather climates due to freeze-thaw action.

However, there is some debate over whether silane-siloxane sealers offer increased durability for masonry or concrete structures. While some experts argue that it does improve durability by providing a waterproofing agent and protecting against weathering, others suggest that these sealers may actually increase damage due to their inability to penetrate deeply enough into the material. Ultimately, this issue is still under debate and needs more research before a clear consensus can be reached.

That being said, the benefits provided by silane-siloxane sealers often outweigh any potential drawbacks. Applying a sealer will help ensure your masonry or concrete structures remain strong and durable for years to come.

Next we’ll take a deeper dive into just how effective silane-siloxane sealers are when it comes to providing protection against water penetration.

  • Studies have demonstrated that silane/siloxane sealants penetrate and protect up to 1 mm into concrete and masonry, allowing them to reduce water absorption.
  • The hydrophobic nature of silane/siloxane sealers helps repel dirt and contaminants, resulting in cleaner surfaces.
  • Silane/siloxane sealers can help inhibit corrosion of metals embedded in concrete, such as rebar and wire mesh.  

Protection from Water Penetration

When it comes to using silane-siloxane sealer to protect a home, one of its most important features is the protection it provides from water penetration. It is a hydrophobic mixture that works by blocking water absorbency and preventing any moisture from seeping into a structure or material.

In general, homes benefit from a waterproofing sealant like silane-siloxane because it can help extend their longevity and keep them in better physical shape for longer. As water infiltration can lead to severe damage including rotting wood beams, rusting of metal parts, and loosening/cracking of masonry components, having a dependable sealant acts as an extra layer of defense.

On the other hand, there are some potential drawbacks. One is that with intense storms or flooding conditions over time, the sealant can wear down and defeat its purpose. While regular maintenance can help with this, it should still be taken into consideration when evaluating the value of applying this type of sealant. Furthermore, if there are existing structural defects due to aging or other factors in a home before the sealant is applied, then this too could affect how effective it is at keeping out water.

Ultimately, while silane-siloxane sealer is helpful in protecting against water penetration, homeowners should also be aware of any preexisting issues that could remain despite applying the product so they know what extra steps may need to be taken to ensure ongoing protection and security for their home. With this in mind, we now turn our focus to application of silane-siloxane sealer – the next step in our comprehensive guide.

Application of Silane-Siloxane Sealer

Silane-siloxane sealers should be applied to your home’s exterior surfaces to ensure your home’s protection from the elements. Appropriate application of this sealer allows it to penetrate into the substrate, where it will bind to both the masonry and moisture present in order to form a hygroscopic coating that is capable of repelling water from your home and resisting the damaging forces of extreme temperatures.

The most reliable way to properly apply the sealer and ensure maximum protection for your home is through a professional application, as experts are well-versed on proper procedures and will be able to guard against any potential application errors or inconsistencies.

On the other hand, if you choose to apply the silane-siloxane sealer yourself, it is important to follow certain guidelines. Before doing so, use a small breathable sample of masonry and apply the sealant with a low pressure sprayer or 3/8th nap non shedding roller. Start from the bottom of the wall and apply liberally and evenly; it is recommended to move up approximately three feet before moving over for even coverage. In addition, avoid application on rain soaked surfaces as well as when there are high temperatures or strong winds; these conditions may reduce effectiveness of the sealant.

Be sure to not disturb previously applied coatings either by abrading the substrate or applying solvent-based materials.

Overall, an effective application of silane-siloxane sealer can last up to ten years while at same time being resistant to water penetration, dust, dirt, mold, mildew and other weather damaging elements so long as it has been properly applied. Now that we understand more about applying this sealer, let us discuss another important factor in its success – substrate material.

The Substrate Material

The substrate material is an essential factor to consider when determining whether to apply silane-siloxane sealers. The term “substrate” refers to what lies beneath the sealers, such as concrete, brick, stucco, stone, wood and asphalt. The type of substrate will determine which type of product is best suited for protection of your property.

Using products specifically designed for masonry substrates (like concrete or brick) on wooden surfaces could have devastating results. For example, an acrylic-based sealer formulated for masonry surfaces can result in swelling and cracking of the surface if used on an untreated wooden surface. On the other hand, a water-based sealer formulated for wood will not adequately protect masonry substrates due to its lower durability and resistance to UV exposure.

It is therefore important to use products that are specifically formulated for your particular substrate in order to maximize protection and longevity. A professional contractor should be consulted in order to select the appropriate product for installation and application.

Now that we have discussed the substrate materials, let us now look at the pros & cons of silane-siloxane sealer in the next section.

Pros & Cons of Using A Silane-Siloxane Sealer

Silane-siloxane sealers, also known as water repellent sealers, are one of the most reliable ways to protect your home from damage caused by moisture. This sealer is made up of silane and siloxane molecules that form a protective barrier against water intrusion and surface damage. When applied properly to masonry, bricks, stucco, or concrete surfaces, it can extend the longevity of your home’s exterior.


There are many benefits that come with using Silane-siloxane sealer. First and foremost, as previously discussed, this sealer is successful in blocking out water intrusion and preventing freeze-thaw cycles in which moisture expands and cracks through the porous material. Aside from its protective properties, silane-siloxane sealer does not change the appearance of the surface it is applied to once dried, making this type of waterproofing a aesthetically friendly choice. Furthermore, this sealer is fairly easy to apply using either a sprayer or roller, plus it is more cost effective than other alternatives such as membrane coatings.


While silane-siloxane sealers provide numerous advantages, there are a few disadvantages associated with them as well. For instance, because it does not create an impenetrable barrier around the substrate like other types of waterproofing materials do – such as polyurethane or acrylic film forming topical sealers – water can still penetrate into the substrate itself when pressure builds up against the surface. To counteract this problem, experts recommend re-sealing the area every 2-3 years to ensure that proper protection is provided on an ongoing basis. Additionally, while this material works wonders on porous surfaces such as brick or concrete block walls; it’s less effective on surfaces with low permeability due to high surface tension between them and the sealer itself.

Overall silane-siloxane sealers have a beneficial place in protecting your home from water infiltration. However, like all solutions they have their drawbacks so understanding how effective they are under certain conditions will help you make an informed decision when it comes time to protect your property from weathering effects like seasonal rains or freeze/thaw cycles. With that said, let’s move onto our conclusion.


The use of a silane-siloxane sealer can be an effective way to protect and seal your home. The protection of your home’s walls, surfaces, and other areas is important not only to preserve the strong foundation but also to prevent moisture penetration and mold growth. Silane-siloxane sealer has proven to be an incredibly effective barrier which can be used on a variety of surfaces, protecting them from water damage, UV light damage, and cracking.

Though there are many surface sealers available, silane-siloxane sealer offers unbeatable features such as low cost, high levels of protection, longevity, and the ability to be used on a range of surfaces such as wood and concrete. This sealer is also authorised for use in residential areas by governmental organisations such as the EPA. Therefore, if you are looking for an effective way to protect your home that is both inexpensive and backed up by governmental authorisation, then silane-siloxane sealer could be the solution for you.

Before making the decision to use any kind of protective coating it is important to weigh up both the pros and cons associated with it. As with any kind of product there may be certain limitations or risks when using this type of sealer. For example, silane-siloxane may require additional preparation when used on certain stone or masonry surfaces so it is important to conduct research prior to use. Additionally, this type of sealer cannot be applied over previously painted surfaces so they would need to be stripped beforehand.

Overall, silane-siloxane sealer can provide a cost-effective solution for protecting various aspects of your home against water damage, UV light damage, and cracking without sacrificing too much time or money. However, although this product does have merits it is important that research into its usage is conducted before application in order to avoid any potential risks or issues during the process.

Answers to Common Questions

What surfaces can a Silane-Siloxane sealer be used on?

Silane-Siloxane sealers are a fantastic choice for use on almost any substrate, including porous masonry, stucco, concrete, brick, and natural stone. They provide reliable protection from water damage due to their hydrophobic nature—meaning they repel moisture. The sealer also prevents dirt, dust, and other contaminants from penetrating the surface of the material, preventing discoloration and prolonging its lifespan. Furthermore, Silane-Siloxane sealers are UV-resistant and can be applied in temperatures as low as 40°F with minimal agitation. As such, they can be used to protect just about any kind of porous mineral based surface imaginable!

How do you apply a Silane-Siloxane sealer?

Applying a silane-siloxane sealer is relatively easy and straightforward. First, you’ll need to prepare the surface by cleaning with a degreaser and water, then rinsing it off with a garden hose or pressure washer. Allow the surface to dry completely before beginning application. You’ll also want to stir the sealer and then pour it into a pump sprayer for easier application.

From here, simply apply an even coat of silane-siloxane directly to the surface using even coverage. If the surface is very porous apply a second coat in the same manner. Once applied, allow the sealer to dry for at least 4 hours before exposing it to any foot traffic or weather. Following these simple steps will give your home the best protection while lasting for years!

What are the benefits of using a Silane-Siloxane sealer?

Silane-Siloxane sealers are a high-performance option to protect homes from water, air and environmental damage. Concrete and masonry surfaces, such as brick, stucco, exterior walls and driveways, can benefit from the barrier that a silane-siloxane sealer provides. With this type of product, homes can be protected from freeze thaw damage, UV damage, cracking and discoloration, mold and mildew, caused by moisture in the surface. It also provides a low VOC (volatile organic compound) solution with minimal impact on indoor air quality.

Other benefits include providing maximum water repellency with minimal surface darkening and maintaining breathability of treated substrates due to its ultra-low film build properties. Additionally, Silane-Siloxane sealers are highly resistant to dirt pickup and are easy to apply requiring one coat only. This helps reduce labor costs and time associated with application.

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