Fill the Gaps with Polymeric Sand

Polymeric sand is to hardscaping what grout is to stone veneer. It fills the gaps between each stone, adding an attractive, durable border that protects the structural integrity of the mosaic.

Polymeric sand is what it sounds like: grains of sand mixed with polymers that bond together once mixed with water. While it is not the only type of material used for filling joints – standard fine sweeping sand is still more widely used by installers – it offers advantages that make its modestly higher price point worth it. 

Stop Weeds and Ants

Among them, joints filled with polymeric sand can stay intact for up to a decade. Unlike standard sand fill, they are resilient in the face of heavy rains, winds and freeze-thaw cycles, and can’t easily be picked apart by ants.

Patios and walkways sealed with polymeric sand are also less likely to suffer weed outbreaks. Because the grains are bonded tightly together like cement, vegetation can’t push through like they can with loose fill and seeds won’t have cracks to seep through. Once weeds get established, they can spread rapidly and become tough to control.

 “Every spring I would go out thinking I could knock the weeds out in one day, and then you realize just how many joints there are. And I’d say wow, I did not anticipate this being as hard as it is,” Instone Video Producer Ken Czechanski recalled of his old patio, which did not use polymeric sand. “It’s long and arduous to sit there on your knees scraping them out.”

Additional Benefits

In a recent episode of InBuilding Design, Czechanski welcomed the crew to his Chicago area backyard to chronicle the replacement of his cement paver patio with one made of Aura Natural Landscapes natural stone pavers. Another benefit he’s noticed to using polymeric sand is its ability to protect the base of the patio. As seen in the episode, his old patio had multiple loose pavers that presented a trip hazard and pooled water during storms. Just as potholes form when water freezes and melts beneath the roadway, excess water seeping through your joints in the winter can chip away at a patio’s stability. Czechanski immediately noticed that the polymeric sand was helping control stormwater more effectively.

“When it rains, as soon as it stops, you can see the stones begin drying immediately,” he said. “Polymeric sand is protecting the base and preventing the stones from shifting.”

Polymeric sand is available in a variety of color blends, giving contractors plenty of options to fulfill the desired look of the project. Czechanski considered three colors that could serve as an accent to his Aura Sandy Point granite stones – a gray, a tan, and a brown.

“We ended up going with the brown because it provided a nice contrast to the stones, which were lighter like the beach,” he said. “It also helped to highlight the pattern, which had brown speckles in it.”

Installing Polymeric Sand

Filling joints with polymeric sand is simple. As seen in the clip above, the first step is to pour the sand onto the patio and use a broom to sweep it into the gaps. Excess sand is carefully swept off the patio to ensure it won’t bond to the stone face later.

Once the joints are properly filled, the installers wet the patio down with a garden hose on a shower setting – strong enough to rinse off any residue, but light enough that it won’t blast out the sand. The water activates the polymeric sand and makes it bond together.

Try out Color Combinations

You can use the Instone Visualizer to help select a stone and polymeric sand combination that’s right for your project. The online tool enables you to upload photos of a property and instantly simulate what it would look like with Instone’s full range of products.

Although Instone doesn’t carry polymeric sand, the Visualizer does model several colors to give users a sense of how it would look with various stone types. Customers may purchase polymeric sand through their dealer or browse product choices at a local home improvement store.

When it comes to hardscaping choices, applications matter. A property owner may have their heart set on a stone color or finish, but there are times when the available options would be a poor match for the project.

“For a front walkway, you want something that complements the house and front steps, since it’s a focal point,” Instone Vice President of Natural Stone Products Justin Alicandro said. “For a patio, the homeowner can go with whatever they like best because you don’t typically have limitations. But for a pool, you are limited. It’s not as simple as picking a color you like and going with it.”

When limitations stand in the way of a client’s vision, it’s up to masonry, landscaping, and hardscaping professionals to educate them and present options for a plan B.

Justin Alicandro, VP of Natural Stone, Instone

Alicandro offered some key guidelines that buyers and installers should keep in mind when choosing the right natural stone for their projects.

Budget First

A good first step for any project is for property owners to assemble as much information about the job site and their goals as possible to get the most accurate estimate. If installing a patio, they should measure the space, take pictures of the construction area, and provide it to the dealer. A professional can spot details like undulations in the turf that will require extra grading that impacts the cost.

With that done, the client will be better equipped to select a product that fits into their overall budget. Instone carries the largest selection of natural stone in the country, from fine, hard-to-find products available at the highest price point to similar-looking alternatives that cost much less. Alicandro estimates that there can be a 30 percent difference between the most and least expensive natural stone products. With patio projects often topping 1,000 square feet, the material choice can significantly affect the bottom line.

Pool Decking

When it comes to surrounding a pool, buyers should think with their feet. Since these areas will be enjoyed with no shoes on, it’s best to avoid finishes that are rough to the touch and stone types that will generate too much heat. Stones with natural finishes can be abrasive, become stubbing and trip hazards, and trigger accidents with children. It’s also best to avoid dark stones that attract the sun – think of the difference between walking on black asphalt and a white sidewalk in the summer. Light color stones like travertine and quartzite are beautiful and more practical.

Alicandro said homeowners often splurge on elaborate pools with top-of-the-line mechanical infrastructure but talk themselves into saving money by using concrete stamp decking. He urges them to resist the temptation to skimp at the end of the project.

“If you’ve already spent $150,000 on pool construction, spend the extra 10 percent or so and go with what you love, and that’s natural stone,” he said. “At the end of the day, this is what your family, friends and neighbors are going to see.”

Finishes

Customers should consider the pluses and minuses of the available stone finishes for their specific project.

Natural Cleft: Many would argue that natural cleft is the most beautiful, natural-looking finish on the market. That doesn’t mean it’s the right choice. For those living in cold northern climates, the bumpy, tough surface can make it difficult to shovel snow when used as a walkway stone. It is also rough on the feet as pool decking and its unevenness can cause furniture to wobble as a patio stone.

Honed Finish: A high percentage of stones with honed finishes are used for pool decking since it’s comfortable to walk on. Stone with honed finishes are sensitive to exposure to snow salts, though, so they are not advisable for walkways. Since patios aren’t used often in the winter, these finishes can be a sensible choice.

Thermal Finish: The most popular finish of all, thermal has a natural, textured look and feel. It is practical in just about any application – it can be salted, it’s easy to clean, and has the fewest number of drawbacks.

Stairs Treads and Sills

Natural stone stair treads are typically placed on top of a veneer, so it should either complement or contrast well with the other material. Although buyers should consider how the stairs will be used when selecting a finish (e.g., will people walk it barefoot, will it need to be shoveled), the selection is less about the physical and more about what looks right with the stone or veneer used for its base.

The choice considerations are similar for natural stone windowsills. For example, Alicandro said a popular trend of late has been to go bold with a black sill over a gray veneer. Sills are all the same basic size and shape, he noted, so the choice is largely one of aesthetic preference.

Outdoor Kitchens, Fireplaces and Firepits

Choosing the right stone for outdoor kitchen, fireplace and firepit areas is similar to selecting stone for sills. Since these heated gathering places all typically sit on top of patios, the stone styles should complement one another. If an outdoor kitchen is added to an existing patio, veneers should be selected that work well with it. If they’re all being installed at the same time, the color choices should be coordinated in advance.

Careful consideration should be given to the stone used for an outdoor kitchen’s countertop, though. It is possible for oils and wines to stain stone, so a dark color is the safest bet. But if a lighter stone is desired, Alicandro recommends going with thermal and leathered finishes. The thermal treatment will give it a textured feel, while the leathering adds an antique look that makes it harder to stain.

Getting Started

Homeowners can consult their local stone dealer or supplier for recommendations on materials and top local installers. Dealers will have a list of businesses who they’ve worked with and received positive reviews from their customers. Contact Instone today to learn about dealers in your area or visit Instone’s Aura Natural Landscapes page for catalogs and videos featuring our wide variety of natural stone products. 

For more help with your dream exterior home project, visit our blog on the do’s and don’ts of planning a backyard makeover.