Stone and Tile Blog: February 2023

Tuesday, February 28, 2023

Choosing the Right Floor Pad for Your Stone: Key Considerations Before Buying Buffing Pads

Choosing the Right Floor Pad for Your Stone: Key Considerations Before Buying Buffing Pads

By Frederick M. Hueston, StoneForensics.com

Keep in mind that every floor pad has a particular purpose and shouldn't be used on every type of stone. The following are some important queries to make before buying buffing pads.

I have what kind of stone am I polishing? Is it marble, granite or whatever?

What type of tasks am I doing? Polishing, cleaning, heavy-duty cleaning, removing a coating

What size pad do I need? Can I use a larger pad than my pad driver.

All these questions need to be answered in order to select the right pad for the task at hand.

Method of Color Coding for Floor Scrubber Pads

In order to make it easier for you to understand how harsh a particular pad will be on your floor; floor pads have an industry-standard color-coding scheme. Darker colored pads are often more aggressive, whereas lighter colored pads are thought of as light duty. Because they are used to buff at extremely high rates, floor burnishing pads generally be aggressive despite not adhering to the industry standard color-coding system.

White

The softest floor pad you can choose from is a polishing pad, which works well for daily duties. To give your floors a smooth finish, use white polishing pads with a low-speed floor polisher and a fine water mist. White pads are often used as the final dry buff after the stone has been polished. They can also be used in place of steel wool with some crystallization polishing systems. White pads can also be used with stone polishing powders but often are not aggressive enough to achieve an acceptable shine. White polishing pads are not made for high-speed machines and won't hold up on rough surfaces.

Red

Red buffing pads produce a brilliant polish and sheen while removing minor scuffs and grime from stone flooring. For light-duty use, buffing pads are ideal because they won't harm most stone flooring. They are made for a low speed buffing machine and are suited for the majority of daily cleaning activities. Some red pads will bleed with polishing powders that contain oxalic acid So I would avoid them for use with these powders.

Green and yellow

These pads are more aggressive than the red pad but not as aggressive as the black pads. They can be used to remove heavy soil along with heavy duty cleaners as well as for stripping light coatings. They can scratch the surface of marble and limestone, so care is required.

Black, Brown and Purple

These pads are used to completely remove finish, sealant, waxes, and grime. These should only be used with low-speed machines since they are quite abrasive and harsh and will scratch most marble and limestone flooring

Stripping pads are typically black, however they can also be found in purple and brown. You can select the ideal color stripping pad for you based on the type of floor stripping you are performing.

Burnishing Pads

Burnishing pads are used on high-speed buffers for burnishing certain wax finishes. However, they are the mainstay for polishing marble, limestone and other stone surfaces using a 175-300 rpm buffer. They are just abrasive enough to generate the right amount of heat along with standard polishing powders to produce a factory shine. These pads go by many names depending on the manufacturer, but most all are generically called hogs hair pads.

Diamond Impregnated Pads(DIP)

These pads are used for resurfacing marble and other stone types. They are impregnated with diamond abrasives and are available in various grit sizes ranging from 100 to as high as 11000 or more. The higher grits can be used on a burnisher but the lower grits generally work best on a standard 175-300 rpm buffer.

Not all manufacturers stick to the industry’s color-coding system so make sure to ask what the recommend use is for from each pad.

Pad sizes

Pads sizes are typically sold in a 16 -22 inch size but you may find other sizes as well. Small sizes, less than 16 inches, can be hard to find but you can always cut down a larger pad to fit small drive plates.

Buffing Pads are an essential tool for restoring and maintaining the shine and polish of marble, granite and most stone surfaces. By selecting the correct pad for the job, you can ensure that your natural stone surfaces remain in pristine condition for years to come. Remember to always follow the manufacturer's instructions when using these pads, and if in doubt, seek advice from a professional.

Quartz vs Quartzite Countertops

Quartz vs Quartzite Countertops

By Frederick M Hueston, StoneForeniscs.com

When it comes to kitchen countertops, there are numerous options available, ranging from natural stones like granite and marble to engineered materials like quartz and quartzite. Two such popular options are quartz and quartzite countertops. While their names might suggest a similarity, these materials are vastly different in their composition, durability, and maintenance requirements.

Quartz countertops are an engineered material that combines quartz particles (usually about 93%) with resins, polymers, and pigments. This mixture is then molded into slabs, which are used as kitchen countertops. The primary benefit of quartz countertops is their durability, as they are scratch-resistant, heat-resistant, and non-porous, which makes them resistant to stains and bacteria. They are also available in a wide variety of colors, patterns, and finishes, allowing homeowners to achieve their desired aesthetic.

On the other hand, quartzite countertops are a natural stone product formed from the metamorphosis of quartz sandstone. This natural process creates a hard and durable material that is resistant to heat, scratches, and etching. One of the primary benefits of quartzite countertops is their unique veining and color patterns, which add a distinctive character to each countertop. Quartzite countertops are also resistant to bacteria and staining, making them easy to maintain.

While both quartz and quartzite countertops are durable, there are several key differences between the two materials. Quartz is an engineered product, which means it is not a natural stone. This can be a downside for homeowners who are looking for an all-natural product. Additionally, while quartz is non-porous, it is not completely heat-resistant, and exposure to high temperatures can cause discoloration and damage.

In contrast, quartzite is a natural stone product, which makes it a popular choice for homeowners looking for a natural and unique look for their kitchen countertops. It is also heat-resistant and non-porous, making it a low-maintenance option for homeowners. However, due to its natural formation, quartzite can be more expensive than quartz.

When it comes to maintenance, both quartz and quartzite countertops are relatively easy to clean and maintain. Quartz countertops can be cleaned with mild soap and water, while quartzite countertops require regular sealing to prevent staining and etching.

In in both quartz and quartzite countertops have their unique benefits and drawbacks. Quartz is an engineered product that is available in a wide variety of colors and finishes, is scratch-resistant, and requires minimal maintenance. Quartzite is a natural stone product that is heat-resistant, has unique veining and color patterns, and is low-maintenance. Ultimately, the choice between quartz and quartzite countertops will depend on individual preferences, budget, and lifestyle.

Frederick M. Hueston
www.stoneforensics.com

office 321 514 6845

For more details see the training section at www.stoneforensics.com

check out the Stone and Tile Radio Show at http://www.blogtalkradio.com/drfred Airs every Wednesday at 6pm EST

Video blog- https://www.youtube.com/channel/UCaXeHDTeUD28j2AJsaNAqTQ?view_as=subscriber

Facebook https://www.facebook.com/stoneforensics1

Article Blog stoneforensics.blogspot.com

My other home improvement articles: https://fredsshed.wixsite.com/website/blog

Tuesday, February 21, 2023

Getting Into the Concrete Polishing Business

Getting Into the Concrete Polishing Business

By Frederick M Hueston, StoneForensics.com

The market for concrete polishing is expanding and presents a lucrative opportunity for business owners starting new ventures or those in the stone polishing business. Because of its toughness, ease of upkeep, and aesthetic appeal, polished concrete floors have seen a considerable rise in popularity in recent years. Here are some pointers to get you started if you're thinking about beginning a concrete polishing business.

Examine the market and rivalries.

Any company venture should begin with market and competitor research. You must be aware of your competitors' strategies, your target market, and their purchasing power. Find out which sectors and company models are most likely to utilize polished concrete floors by conducting some market research. Moreover, look into the competitors to discover what services and rates they provide.

Get the required knowledge and tools.

Specialized tools and abilities are needed for concrete polishing. A concrete grinder, diamond pads, a dust collection system(if dry polishing), etc. To achieve the finest outcomes, you'll also need to know how to use these tools efficiently. Consider enrolling in classes or training sessions to gain the required knowledge, and make superior equipment purchases to guarantee you can produce outcomes of the highest caliber. One such company is MB stone(https://www.mbstonetraining.com/training/mb-stone-professional-concrete-repair-class/)

Get the required permits and insurance.

Prior to opening your concrete polishing company, you must acquire the required permits and insurance. You might require a contractor's license, a business license, and liability insurance, however this will depend on where you are. Before starting your firm, be sure to do your research on the regulations in your region and acquire the required permits and licenses.

Create a powerful network

A robust client base, supplier base, and contractor network are essential for a successful concrete polishing firm. Begin by establishing connections with other construction industry experts including architects, builders, and interior designers. Attend trade exhibitions and industry events to network with possible customers and suppliers. To reach potential clients, you can also use social media and internet advertising.

Provide top-notch client service

Every firm needs to provide excellent customer service, and the concrete polishing sector is no exception. Be sure to be transparent with your clients, control their expectations, and produce high-caliber work. If you offer top-notch customer service, you will earn a reputation as a dependable company that customers will keep coming back to.

For business owners with the required abilities and resources, starting a concrete polishing company can be a successful opportunity.

The Importance of Installing Expansion Joints In a Stone/Tile Shower: What You Need to Know

The Importance of Installing Expansion Joints In a Stone/Tile Shower: What You Need to Know

By Frederick M. Hueston, StoneForensics.com

Have you ever taken a look at the corners of a stone or tile shower and seen that they are all cracked, and in some cases, the grout is completely missing? What about the part of the wall that is flush with the floor? Why does this area have such a propensity for cracking and falling out? The cause is that there are not enough expansion joints or that there are hard joints where there should be soft ones. An important step that needs to be taken before any tiling can be done in a tile or stone shower is the installation of expansion joints in the walls and floor of the shower. The tile must be able to expand and contract in response to changes in temperature, so the installation of expansion joints is required. Tiles are susceptible to cracking and shifting when there are no expansion joints present, which can result in expensive repairs and possible water damage.

The use of expansion joints in a stone/tile shower makes it possible for the tile to expand and contract in response to variations in temperature. When it comes to durability and lifespan, expansion joints are absolutely necessary. If they are not installed correctly, they have the potential to induce cracks in the tile, which will ultimately lead to the tile's early failure. When installing a tiled shower, the joints are placed at the points where the tile meets another material, such as at the intersection of the wall and floor to walls. The joint is filled with a soft caulk such as silicone or urethane, and the amount of caulk used in the joint expands and shrinks depending on the temperature of the region around it. This caulking should be water resistant, mold resistant, and bacterium resistant as well.

Installing expansion joints in a stone/tile shower is a straightforward process inspect the shower for cracks and leaks in the tile or other damage to the walls and floor. You will also want to make sure that the wall and floor are level. remove the old, damaged tile and clean the walls and floor thoroughly.

purchase and install the right type of caulking. There are many types of caulk that can be used and some of them are appropriate for tile and other may stain certain stone. The following is a breakdown of caulks available:

100% Pure Silicone Caulk

The most common type of sealant is silicone caulk, which can also be referred to as rubberized caulking. This caulking is ideal for repairing minor leaks and mold in your shower. It is very easy to apply, it can address all problem areas without any issues, and the rubbery feel stays with it forever, which makes it great for handling the movements in the joints where other options can fracture. Because of these qualities, it is a highly popular choice.

The fact that it can be controlled with relative ease, on the other hand, is the key factor that contributes to its popularity. Silicone caulk may be applied directly to your shower, and because it enables a more accurate application, you won't need to use as much of it as you would with other caulks. This cuts down on waste.

Because of its longevity and resilience to water, it is the superior material to use in a showers, facets, and other similar areas. It is also more resistant to extremes of temperature, both hot and cold.

Silicon caulk is one of the alternatives that often carries a higher price tag than the others. However, if you take into account how long its effects will stay, you will see that purchasing it is money well spent.

The material is incapable of holding paint, but the problem can be remedied by painting over it with a thin coating of siliconized acrylic latex or by using a primer that is based on oil.

Inorganic Latex Acrylic

This is a low-cost, all-purpose caulk that is simple to work with and can be put to use in a variety of different situations. Additionally, it is simple to paint over. Latex is an excellent material to employ in places with a high porosity and is, in general, the more preferred choice because to the inexpensive cost. This material is a great alternative to silicone caulk because it is not difficult to clean (latex is water soluble), and it is readily available. In addition to that, it dries more quicker and, of all the things on this list, it is possibly the most resistant to mold.

On the other hand, its resistance to water is not nearly on par with that of a 100% silicone. Because of this specific reason, it is possible that it is not the greatest choice for the shower.

Since it is not very expensive, you may always continue applying it to cure small concerns, but problems like cracking and flaking will keep recurring often even after repeated applications.

Caulk made of latex or acrylic, combined with silicone

This hybrid variety of caulk is variously referred to as "painter's caulk" and "tub and tile" caulk. It is comparable to acrylic latex, but offers greater flexibility as an alternative, despite the fact that it is not as flexible as a material composed entirely of silicone. Because it contains silicone, this alternative to traditional latex caulk is both more durable and more resistant to moisture than the latter. It can be the excellent substitute for acrylic latex, and it makes painting over it very easy to do. It is perfect for spots that require only a minimal amount of waterproofing.

Even though the packaging indicates that it is resistant to water, it is recommended that you only apply it on the dry areas that are covered in paint so that the exterior can continue to be protected. It is not a caulking alternative that is particularly successful, which is why it is not recommend using it.

PVA (Polyvinyl Acetate) (Polyvinyl Acetate)

This caulking substance is manufactured from polyvinyl and has all of the features of polyvinyl, such as resistance to mold, durability, and heat resistance. It is very similar to the acrylic latex product, which is also made from polyvinyl. PVA is another alternative that can be painted over.

It does not have very good resistance to water and it deteriorates over time.

Expansion joints, when they are appropriately installed, not only prevent future failures but also improve the overall appearance of the installation, which in turn raises its aesthetic value and ensures that it will last for a longer period of time.

The Use of Color Enhancers on Stone Surfaces

By Frederick M. Hueston StoneForensics.com

Natural or artificial stone surfaces are renowned for their sturdiness, adaptability, and beauty. Unfortunately, the hue of the stone may fade or become dull with time due to exposure to the environment and normal wear and tear. Thankfully, there are color enhancers that may bring out the stone's natural tones and patterns, giving it a lively and alluring appearance. We'll go through how to apply color enhancers to stone surfaces in this article.

Recognize the kind of stone surface you have:

The initial stage is to determine the kind of stone surface you have. On various types of stones, color enhancers function in various ways. For instance, some stones, like marble or quartzite, may take more time and effort to get the desired results than others, such as granite, slate, and sandstone, which are very porous and quickly absorb the enhancer. The best color enhancer for the job will be easier to select if you are aware of the sort of stone surface you have.

Choose the proper color enhancer:

Several color enhancer kinds, including penetrating, topical, and wet-look enhancers, are available. The natural colors and patterns of the stone are enhanced with penetrating enhancers, which are absorbed into the stone's pores. Comparatively, topically applied boosters give the stone a layer of defense against stains and abrasions. Wet-look enhancers give the surface of the stone a glossy, polished appearance.

Color enhancers are also available in a solvent or water based carrier. It is best to test both for desired results.

Prepare the stone surface:

It's critical to properly clean the stone surface before applying the color enhancer. To clean any dirt, debris, or stains from the surface, use a pH-neutral cleanser. Clean the surface with water, then allow it to thoroughly dry. Before applying the enhancer, treat any areas with a stone-specific stain remover if there are any serious stains.

Apply the color enhancer:

After the surface has been well cleaned and dried, the color enhancer should be used. Pay close attention to the directions on the product label. Most of the time, you'll need to use a brush or a spray bottle to apply the enhancer. Be sure to uniformly cover the entire surface. To get the desired effect while using a penetrating enhancer, you might need to apply more than one coat. Before touching the surface, let the enhancer entirely dry.

Maintain the stone surface:

It's critical to maintain the stone surface properly to ensure that the color enhancer lasts for a long period. On the surface, stay away from applying strong chemicals or acidic cleaners. For routine cleaning, use a pH-neutral cleaner made especially for stone surfaces. If something spills on the surface, clean it up right once to avoid stains. Moreover, stay away from setting hot pans or pots directly on stone surfaces as this can harm the color enhancer.

Applying color enhancers to stone surfaces can accentuate the stone's inherent beauty and safeguard it from normal wear and strain. To get the desired results, you must select the suitable enhancer and thoroughly prepare the surface. These techniques can help you maintain the attractiveness and vibrancy of your stone surfaces for many years to come.

What is the proper caulk to use on stone and tile

What is the proper caulk to use on stone and tile

By Frederick M. Hueston StoneForensics.com

Choosing the proper type of caulk when installing stone or tile is extremely important. All too often the wrong type can seep into the stone or tile causing staining that can be difficult to remove. So, what type of caulk should be used in your stone or tile countertops, shower etc. The following should help you understand the different types of caulks and where they should be used

Caulk is a versatile material used to fill gaps and cracks in stone and tile surfaces such as walls, floors, and countertops. It is a pliable material that can be used to form a seal that prevents air and moisture from passing through. There are several types of caulks, each with its own set of properties and applications. In this article, we'll look at the most common types of caulks and how they're used.

Silicone

Silicone caulk is widely used for sealing stone and tile corners and wherever there is change in plane in shower walls, floors or countertops. It is flexible, waterproof, and mildew resistant, making it ideal for moisture-prone areas. Because silicone caulk is heat resistant, it can be used around ovens and other high-temperature surfaces. It should not, however, be painted and should not be used on porous surfaces. Only 100% silicone caulking should be used. Avoid any hybrid combinations such as acrylic-silicone types.

Acrylic

Acrylic caulk is a water-based material that can be painted over after it has dried. It can be used to fill gaps and cracks in wood, drywall, and other porous surfaces but should be avoided on stone surfaces. It may be ok for ceramic or porcelain tile. Acrylic caulk is less flexible than silicone caulk and should not be used in moisture-prone areas.

Latex

When a paintable sealer is needed in some areas, latex caulk is a popular option. It is a great alternative for filling gaps and cracks in drywall and wood that abuts tile because it is water-based, simple to use, and easy to apply. Since latex caulk is less flexible than silicone caulk, it should not be used in locations where moisture is present. This type of caulk is not recommended for stone surfaces.

Butyl

Butyl Caulk Butyl caulk is a synthetic rubber substance renowned for its superior adhesion capabilities. It works well for sealing exterior tile, and other outdoor applications. Because butyl caulk is adaptable and weatherproof, it is perfect for usage in outdoor spaces. It should not be painted, though, and it should not be used on porous stone surfaces.

Polyurethane

polyurethane caulk is well-known for its superior adhesive qualities. It works well for patching up holes and cracks in masonry surfaces like concrete, brick, and others. In addition to being flexible, polyurethane caulk can be used in moving spaces and for expansion joints. On the other hand, it is not advised to use it on other porous stone surfaces, and it cannot be painted.

Caulk is a multipurpose substance that can be used to patch holes and cracks in a variety of stone and tile surfaces. Your choice of caulk will be influenced by the surface you are sealing as well as the environment it will be in. There is a caulk kind that will suit your demands, whether you require a flexible, watertight sealant for a bathroom or a strong adhesive for outdoor uses. The best silicone to use on stone is usually 100% silicone, though I would always suggest testing it beforehand to be sure.

Saturday, February 18, 2023

Is cleaning stone with just plain water a good idea?

Is cleaning stone with just plain water a good idea?

By Frederick M. Hueston, Stoneforensics.com

I've lost count of the number of times I've asked homeowners or building maintenance workers what they use to clean stone surfaces, and they've said nothing but water. They appear reluctant to use any kind of cleanser for fear of ruining the stone. I'll explain why using just water to clean isn't a good idea in the next section.

The cleaning chemicals we use on stone surfaces can have a major effect on our health and the environment, yet cleaning is an integral part of proper maintenance. Many people nowadays, in an effort to reduce their environmental impact, are choosing to use solely water. Water alone may seem like a fantastic cleaning solution, but there are really a few reasons why this isn't the case.

Dirt and grime can't be washed away with just water. It's true that water is necessary for cleaning, but it's also true that it won't do a good job of getting the grime off. Frequently, dirt and grime are embedded in the stone surface, making it impossible to remove them with just water. Water alone as a cleaning agent may actually spread dirt and bacteria around instead of eliminating them.

Viruses and bacteria can survive in water.

Even though water cleaning might get rid of obvious filth and grime, it won't do anything to destroy germs and bacteria lurking in the background. Using a disinfectant cleaner or a cleaning product with components specifically safe for stone surfaces is the best way to get rid of germs and bacteria on stone surfaces. It's especially crucial to use these substances in high-traffic areas like kitchens and bathrooms, where the spread of germs and bacteria is constant.

Stains may need more than just water to be removed. Certain stains, like those found on natural stone floors and countertops, are nearly impossible to wash out with just water. Oil and grease stains, for example, may be removed with a poultice that includes a degreaser or solvent. When cleaning these types of stains, using merely water can actually make the problem worse.

In conclusion, cleaning stone surfaces with water alone is not a good method. Only special cleaners can eliminate germs and filth, while water alone will leave stains intact. In order to remove dirt and germs from your stone, you should only use cleaning products that are made for that type of stone and have the right chemicals.

Thursday, February 9, 2023

Epoxy vs. Polyester

Epoxy vs. Polyester. Are You Using The Right Adhesive?

Frederick M. Hueston

I was sitting in my office when I received a call from a hotel manager about a swimming pool coping that was falling apart. I asked him what was falling apart and he told me that the stone was falling into the pool. I got in my truck and made my way over to the hotel and discovered that the swimming pool had a travertine coping and all the laminations where failing and falling off. I examined the laminations closely and discovered that Polyester was used in the laminations.

Several weeks later I got a similar call from a home owner who had a similar problem but this time the laminations where failing on her new granite countertop. Again, upon inspection, the adhesive used was polyester.

How many of you use polyester for your laminations and other applications where you are bonding two pieces of stone together? If you do, your laminations are prone to failure.

There are many choices when it comes to the selection of adhesives and it can get very confusing. The following is a brief explanation of the two most popular adhesives in the stone industry and a guide as to where to use what type:

Epoxy or Polyester?

Polyester

Polyesters use a hardening agent to catalyze the curing reaction. Most polyesters use a peroxide hardening agent.

Of all the adhesives available polyester is the least inexpensive but also has the weakest bond strength. It also has a very high shrinkage rate and the highest water absorption amongst all the adhesives. It is also very prone to UV degradation and will crack and become brittle.

For this reason polyester should never be used for laminations or for repairs in wet area or used outdoors.

Polyesters are good for small repairs for indoor stone applications such as filling and seams or in applications where bond strength is of no concern. The bond strength of polyesters is less than 500 PSI.

Epoxy

Epoxies are two parts labeled part A and Part B. Most epoxies are mixed at a ratio of 2/1 but some are 1/1.

Of all the adhesives used in the stone industry epoxies have the strongest bond. Bond strengths can exceed 2000 PSI. It has a lower shrinkage rate than polyester and is more UV stable with a lower water absorption rate.

It is clear that if you want great adhesion, epoxy is the stronger adhesive. I always recommend using epoxy for laminations and rodding and anywhere else you want the stone to stick and not fall apart.

A little experiment.

Here is a crude test that I perform when testing adhesives for bond strength.

Take two pieces of stone with the polished sides facing each other. Place some adhesive on the polish faces and clamp them together. Let the clamped pieces set overnight. The next morning take a hammer and try to break them apart. A weak glue, such as polyester will break clean, leaving the face of the stone intact. A strong adhesive such as an epoxy will be so strong that the face of the stone will spall off. This indicates that the adhesive bond is stronger than the natural bond of the stone.

Adhesive Grades:

All adhesives are available in various viscosities ranging from low to high. The following are the most popular choices

Knife Grade- Consistency is similar to spackling putty or creamy peanut butter.

Flowing Grade- Consistency of a motor oil

Penetrating Grade- Consistency of water

Super Penetrating Grade- Consistency of a solvent such as mineral spirits or paint thinner

Generally knife grades are used for repairs for fills that are over 1/16 of an inch wide. Flowing grades are used for repairs smaller than 1/16^th and for laminations and rodding.

Penetrating and super penetrating grades are rarely used by fabricators but are used for resining stone and for applications where an adhesive is need to penetrate very small pores.

Adhesive Colors

Today’s adhesives are available in a number of colors however there may times when you need to add coloring. Many of the adhesive manufacturers have tints that you can use. If you in a pinch I have found that artist oil colors work well for most polyesters, however for epoxies you will need to use tints designed specifically for them.

General Properties

Temperature

All adhesives are sensitive to temperature and humidity. This means that cure times will vary. Adhesives will cure faster with increasing temperatures and slower at cooler temperatures.

Temperature will also affect the viscosity. Higher temperature will thin the adhesive.

Tip: There are several heated dispensers for epoxies that work very well for faster cure times and easier flowing.

Cure Time

The general rule of thumb for most adhesives is the slower the cure time the stronger the bond. Epoxies with a 7 hour cure time are going to be much stronger than an epoxy with a five minute cure time.

If too much hardener is added to polyester you will increase the cure time but you will reduce the bond strength.

UV exposure

Nothing is completely UV proof; however epoxies are more UV resistant than polyesters and are the adhesive of choice for outdoor exposure.

Moisture

Polyester is very sensitive to moisture and for that reason it should be avoided in wet areas such as showers. Epoxy has a much higher tolerance for moisture and is the adhesive of choice in wet areas.

When using polyester you must make sure that the stone is completely dry. Epoxies can tolerate some moisture.