Permeable Pavers Blog

With such a variety of materials available for hardscaping — from slate to river stone, and from concrete to steel, why has Unit Paving chosen to specialize in permeable pavers? Why, for that matter, do so many of our customers choose this option over all their others, and what do they see that you might be missing? Good questions, one and all. Let’s dig into the answers.

What Are Permeable Pavers?

Pavement exists in two forms, impervious and pervious. The former is meant to keep water from flowing through, instead diverting it elsewhere. Pervious pavement made from interlocking permeable pavers allows water to pass through; from there, it’s filtered through a substrate and the underlying soil, removing many pollutants and returning water to the soil.

The Benefits of Permeable Pavers

Permeable pavers have been in use since the days of ancient Rome — and some of those paved surfaces endure to this day in the many places where the Roman Empire built its roads. Your paved surface may not last for thousands of years, but neither should you worry about its durability.

Permeable pavers are also environmentally friendly and sustainable. You can get LID and LEED credits for them because they reduce stormwater runoff, reduce the heat island effect, limit the need for complex drainage, and even treat rainwater that’s contaminated by oil, fertilizer, and other pollutants.

How You Can Use Permeable Pavers

Permeable paver products are highly versatile. We take them for granted in some applications like residential walkways and driveways. However, their durability makes them suitable for commercial and municipal use as well. That includes parking lots, pedestrian plazas, and even roads with a high volume of traffic.

But it doesn’t stop there. The large number of colors, shapes, and textures available mean that those same pavers can be used to build an enclosure for your barbecue grill, a durable retaining wall, a fire pit, and numerous other hardscaping designs.

Permeable Paver Costs

You might think that something which manages to be versatile, durable, and attractive must also be expensive. However, when you’re weighing the cost of permeable pavers, it helps to look at the big picture — especially relative to traditional materials like asphalt and concrete.

Concrete and asphalt paving have a reputation for being durable, quick, and inexpensive. The truth is somewhat more complex. Site preparation is more time, labor, and material intensive than it is for permeable pavers. That, in turn, leads to higher prices. Furthermore, a permeable paver surface requires less finishing in the short term and less maintenance in the long term. Both of those things save money.

Permeable Pavers from Unit Paving

With so many benefits, it should be clear why permeable interlocking concrete pavers are a sustainable, durable, and cost-effective choice. However, that isn’t the only important choice you’ll be making; you also need to choose the right pavement contractor, which is precisely why so many in North and South Carolina call on Unit Paving when the time comes for anything from a quick driveway installation to the hardscape design for a ballpark or a city center. We are proud to hold ICPI Certified Installer and Green Advantage Environmental hardscape installer certifications, and — perhaps most importantly — proud of the results we’ve delivered for nearly three decades’ worth of clients. Call Unit Paving today to consult on your next paving project, or for answers to your  permeable paver questions.

If you’re planning a commercial paving project, we hope you’re thinking long-term. That means looking past immediate concerns of planning and cost, and thinking of future considerations like maintenance, drainage, use, and sustainability. We must also confess to an ulterior motive for your foresight; Unit Paving Inc knows from long experience that compared to traditional options like asphalt or concrete, permeable pavers constitute a significant improvement. Here’s why.

Sustainability

With asphalt and concrete paving so popular and so widely-accepted, why has Unit Paving chosen to specialize in permeable interlocking concrete pavers? There are many reasons, but sustainability sits at the top of the list.

They’re called permeable pavers because unlike impervious surfaces, they allow water to pass through the joints, whereupon it’s filtered by the fill and subsurface materials and allowed to pass back into the soil. This limits the need for additional drainage, lowers the strain on existing drainage systems and water treatment plants, and limits runoff because water is sequestered in the ground and pollutants are filtered out instead of ending up in our waterways. What’s more, these pavers mitigate the heat island effect. But even if your concerns are more earthbound, there are more reasons to consider permeable pavers.

Simplicity

If you’ve ever been stuck in traffic during a road construction or repair project, you’ve seen the amount of equipment required to install or maintain traditional paved surfaces. Surface preparation is extensive and complex, large amounts of raw materials must be carted in and subjected to further preparation, and a fleet of vehicles must back an extensive crew of workers to install everything. This process is as expensive as it is extensive.

By contrast, permeable pavers require less surface prep, rely less on expensive equipment, and can be installed quickly by a smaller number of people. The resultant paved surface can handle every bit as much heavy traffic as its traditional counterparts, accommodating everything from foot traffic to cars, trucks, and snow plows with ease. Best of all, it does all this at a significantly lower initial or long-term cost.

Durability

The unique construction of permeable interlocking pavers has another benefit, one you’ve noticed if you’ve been overseas and wandered the remnants of an ancient Roman road, or even walked an old cobblestone street closer to home. High tech has come to PICP, but the principle behind them hasn’t changed much over two millennia. It hasn’t had to; they’re extremely durable, handling large amounts of heavy traffic with ease. Their ease of expansion and contraction helps them resist high heat, extreme cold, and potholes. The fact that they don’t hold water helps prevent flooding, erosion, and potholes. In the rare event that a repair is needed, it can be done quickly by one person equipped with a minimal number of tools.

There’s one last consideration that we haven’t mentioned up to this point: versatility. That’s because the most effective way for us to show you the potential for permeable pavers is to compare our past work with your present and future needs. With this in mind, we urge you to get in touch with Unit Paving Inc for a consultation on your commercial or municipal paving project. We proudly serve clients with commercial paving in the Carolinas, and would be equally proud to serve you.

Even though Unit Paving Inc specializes in Value Engineering through permeable interlocking pavers, we are well aware of one inescapable fact: like any other product or service, ours will not be for everyone. Residential and commercial paving projects take so many different forms that a one-size-fits-all solution would be impossible. However, we’re also well aware that a number of myths surround permeable pavers. If you’re going to make a good paving choice, it should be on the basis of facts, not fiction. Let’s dissect a few of the bigger whoppers we’ve heard over the years.

Site Analysis is a Pain

As long as you’re dealing with an experienced paving company, site analysis is no more complex for permeable interlocking concrete pavers than it would be for any other paving method. A bit of soil testing, load bearing ability analysis, thought given to installation options, and permitting processes is quick and painless. It certainly beats the alternative favored by cheap or less-experienced contractors — namely, a haphazard installation that doesn’t take the pavers’ subsurface into account.

Permeable Pavers Aren’t as Strong

This makes a certain intuitive sense, since an unbroken expanse of concrete or asphalt looks strong on the surface. However, because they’re impervious, those surfaces are actually more vulnerable to damage from stormwater, ice, and other stressors. PICP surfaces are strong enough to bear heavy loads and high traffic.

ADA Compliance is Dicey

Simply not true. As Masonry Design Magazine reminds us, major pavement manufacturers subject their products to rigorous testing for firmness, stability, and skid resistance. As long as your contractor is versed in ADA requirements and installs accordingly — Unit Paving is, and does — you need not worry about whether your paved surface will be compliant with the relevant sections of the Americans with Disabilities Act.

Permeable Pavers are High Maintenance

Nope. Many of your maintenance needs — cleaning, clearing leaves and snow, removing weeds every now and again, dealing with the occasional anthill — aren’t going to be any different with a permeable paving surface than they’d be with traditional concrete or asphalt. In other respects, the fact that permeable surfaces absorb water rather than allowing it to pool and collect means that you’re dealing with lower maintenance because of factors like pollutants, ice, flooding, and the like.

Permeable Pavers All Look Alike

This is perhaps the easiest myth of the bunch to dispel. Permeable paving materials come in a wide variety of shapes, sizes, and colors, just like the rest of the hardscaping materials used by Unit Paving. Not only will you have a plethora of choices, but we can also mix and match colors and shapes to liven up your project to add a bit of contrast and visual interest.

Of course, we cannot possibly cover every last myth you’ve heard or permeable paving question you have in the form of a blog entry. That’s precisely why we encourage you to contact Unit Paving Inc. We bring skill, experience, and taste to your next paving project in the Carolinas.

The Carolinas are two of the original thirteen colonies. We’re reminded of this when severe weather buffets the state, since it can feel like key infrastructure hasn’t had much by way of updates since Charleston was founded in 1670, or when Charlotte was incorporated in 1768. It has, of course, but it hasn’t always kept pace with modern times; many of our cities have modern infrastructure built atop Victorian-era drainage and sewage systems, which can be catastrophic when it comes to managing urban flooding. A key way to prevent this? Permeable pavement installed by an experienced NC paving company like Unit Paving Inc.

Why Flooding Happens

Here’s a thought experiment. Let’s say you go to the soda fountain at your local fast food restaurant or all-you-can-eat buffet, cup in hand, and queue up for a free refill. You decide you’re going to drink while your cup is refilling. If you’re not careful, you’ll be sponging Coke off your shorts. That’s because the flow from the dispenser into your cup is faster than the straw can handle.

Cities’ infrastructure is similar. The storm drains in small towns and big cities alike are like that straw; at some point, the inflow of rain, and the resulting storm water runoff, overpowers even a well-designed system. Our streams, creeks, and rivers crest, and our parking lots turn into swimming pools. With hundred-year and even thousand-year floods happening with greater frequency, it’s clear that something has to give.

How Permeable Pavers Work

Permeable pavers capture stormwater and help the soil absorb it. The more that goes into the soil, the less that goes into storm drains. What’s more, returning water to the soil filters out contaminants, aids in soil retention, and can prevent extensive water damage to paved surfaces and built structures alike. And when flooding can’t be prevented (as happened when Charleston experienced rain by the foot), permeable pavers do a better job of mitigating the impact than impervious pavement.

Permeable pavers are able to do this because instead of a continuous and impervious surface, there are joints filled with a porous compound through which water can pass. It is then filtered through layers of stone that provide the foundation for the pavers.

How Permeable Pavers Prevent Flooding

Now, let’s put it all together. Upgrading infrastructure helps, but it’s time-intensive, disruptive, and expensive. It also doesn’t solve the root of the problem: as development takes hold, and especially once it moves beyond the urban core, more and more of our green spaces are taken over by paved surfaces. Some statistics cite 40% of a cityscape being made up of impermeable pavement.

When the only place for water to go is a city’s storm drains, it places considerable stress on multiple points in that city’s infrastructure. Soil erosion takes place, water runoff introduces chemicals and pollutants to water treatment plants that are ill-equipped to handle them, and flooding is more or less inevitable. Permeable municipal pavement helps minimize that impact and keep cities greener — and drier.

Hardscape Design for Flood Mitigation

Neither North Carolina nor South Carolina are strangers to terrible weather. Our residents are also all too familiar with the flooding that too often follows in its wake. Unit Paving isn’t just well-acquainted with the problem; we’re also on the vanguard of delivering sustainable paving solutions. Our permeable pavers aren’t simply attractive and durable. They’re part of an approach to sustainable hardscape design that is as environmentally-friendly as it is cost-effective. Why not consult with our paving experts today?

Even though Houston is a long way from the Carolinas, the impact of Hurricane Harvey on Texas’s largest city still sent chills up the spine of anyone living in a hurricane-prone area. A combination of overdevelopment and poor wastewater management caused catastrophic flooding and an estimated $180 billion in damage. Not all cases will be this extreme, but homeowners and cities alike are rethinking stormwater runoff management. Permeable pavers like those installed by Unit Paving are one facet of a sensible runoff management plan.

How Permeable Pavers Work

When you understand how permeable pavers work, you can begin to understand how they help to manage stormwater runoff. Permeable paving lays interlocking pavers over a substrate of gravel, crushed stone, or even grass. Small ¾ in. stone is put between the pavers themselves preventing the pavers from shifting but still allowing water to pass through. In contrast to impermeable paving, which sheds water, permeable pavers return water first to the soil, then — eventually — to the local aquifers. This process also filters out pollutants that could otherwise contaminate the local supply of drinking water.

Runoff Management Benefits of Permeable Pavers

Less Municipal System Load

Under normal circumstances, a municipal sewer system can handle a bit of rainfall. However, impermeable surfaces combined with 21st Century infrastructure atop a sewer system built a century ago (or longer) can be a recipe for disaster. Permeable pavers return water to the ground instead of diverting it to storm drains. Sustainable hardscape design using permeable pavers can also limit costs and build complexity, since drainage needs are typically smaller.

Reduced Soil Erosion

Runoff from impermeable paved surfaces undermines the soil in surrounding areas. This is especially true if the paved area abuts a grade or a steep slope. The fact that permeable pavers sequester and filter water means retaining valuable nutrients in the soil, keeping plant life healthy and providing another hedge against erosion. Some paving solutions are also designed for the sole purpose of keeping soil in place, which means less sediment in storm drains, less maintenance, and fewer costly repairs to the surrounding softscape and storm drains alike.

Soil erosion has consequences beyond the potential for desertification. In extreme circumstances, soil erosion can undermine roads, sidewalks, and other paved surfaces. It can also cause costly foundation and structural damage.

Reduced Risk of Flooding

Flooding happens because the volume of water falling or entering an area at any given time is more than drainage systems can handle. Storm drains and pipes will always be a fact of life, but incorporating permeable pavers into a municipal hardscape design reduces the amount of water flowing to those drains, making it easier for them to do their jobs. That, in turn, means less flooding.

Residents of the Carolinas are no strangers to extreme weather. Hurricane season hits harder here than most of the rest of the United States, which makes long-term planning an absolute necessity. Whether you’re a property owner, a business owner, or a municipality concerned with sustainability and stormwater runoff, a permeable paver consultation with Unit Paving can help you manage risk.

When something is nearly ubiquitous, it’s easy to forget it’s there. Permeable interlocking concrete pavers (PICP) are one of those items. They’ve been around for thousands of years, but have become especially popular in recent years. They’ve certainly kept us busy here at Unit Paving Inc, as a growing number of homeowners, businesses, and cities turn to this old tech with a new twist. What’s behind that growing popularity?

Environmental Impact

The United States Geological Survey (USGS) cites a study by the Wisconsin Water Science Center that examines the impact of permeable pavers on the environment, especially in comparison with traditional paving methods. The results of the study were exactly what those of us in the industry would have expected: permeable pavers win hands-down when it comes to environmental impact.

That’s because in contrast with impervious surfaces, a PICP surface is specifically designed to sequester and filter wastewater and return it to the ground. When your landscape or streetscape uses an impervious surface like asphalt, the same wastewater is instead taxing sewer systems; if you’re a homeowner, meanwhile, that water could be pooling on your property, ruining your landscaping and attracting pests.

Sustainability

Of course, environmental concerns dovetail well with sustainability, the design and building methods designed to manage and mitigate environmental impact.

Sustainability addresses the finite nature of our water and material resources. For that reason, hardscaping is intended to return water to the soil rather than the sewer, and relies heavily on recycled and locally-sourced materials. Likewise, sustainable hardscaping like permeable pavers is also part of a wider strategy to preserve local soil and plant life.

Permeable pavers are a good fit here, since the construction method (whereby interlocking pavers are laid down in a grid over gravel, and using polymeric filler) lends itself naturally to erosion control, and limits or eliminates drainage concerns.

Heat Island Mitigation

In addition to its impermeability, blacktop has another significant problem: it absorbs and holds heat. Because permeable pavers are usually lighter in color, their reflective properties can have a light mitigating effect on the heat island phenomenon, whereby paved and overbuilt surfaces have a higher heat than the greener areas around them.

Expense

Interlocking pavers require less complex installation. Typically, the ground can be graded and compacted, a layer of rock or other porous material laid, and the pavers put down over that. By contrast, laying an impervious surface requires specialized equipment and is much more labor-intensive, which drives costs up.

Durability

The interlocking nature of permeable pavers affords an additional benefit: durability. A conventional asphalt driveway or concrete walkway can buckle or crack as the ground settles beneath it, or as tree roots grow beneath the surface. PICP, in contrast, already has a series of expansion joints built in, and rather than being a continuous slab is actually flexible, capable of adapting to topographical changes.

Aesthetics

Let’s be honest. An expanse of asphalt or concrete may be plenty practical, but in terms of looks, it’s about as interesting as watching paint dry. Choosing the right interlocking pavers isn’t just easier on the planet and your landscaping. It’s easy on the eyes.

Whether you’re a homeowner, commercial property manager, or city manager, the benefit of permeable pavers in your green portfolio is obvious. What can be less obvious is who to turn to for the hardscape design and paver installation to modernize your landscape. If you live in the Carolinas, that choice is much easier: simply contact Unit Paving Inc for a consultation and quote.

The Roman Empire is known for its engineering marvels, including aqueducts, public baths, and monumental projects like the Colosseum. One of Rome’s most enduring legacies, however, is also one of its most humble: the paver, passed down through two millennia, and an important part of modern hardscaping. Just as science and experience have improved on other Roman innovations like concrete, the paver has undergone a renaissance of its own, seen in the permeable pavers offered by Unit Paving.

How Permeable Pavers Work

Traditional pavers are impermeable, which is to say they’re specifically designed to prevent the penetration of water. That leads to water — and anything picked up in the water, like oil, fertilizer, and a host of other pollutants — being carried to storm drains, where the whole toxic mixture ends up in our rivers and groundwater.

The alternative is Permeable Interlocking Concrete Pavers, also known as PICP. Instead of being a smooth and solid surface, permeable pavers are designed with a certain amount of porous surface area that absorbs the water. The paver, the substrate, and even the fine stone filler between pavers each contribute to filtering contaminants out of the water before it makes its way back to the soil and the water table.

Permeable pavers should not be confused with pervious pavers such as grass pave. Both are designed for the same purposes, but work by different means; pervious pavers which have a visibly porous look due to their use of a coarse aggregate and larger void areas. Permeable pavers use a different proportion of concrete to aggregate to the same end, but are virtually indistinguishable from other traditional pavers offered by Unit Paving and tend to be more user friendly as well as ADA compliant.

Why Permeable Pavers?

History reminds us that the more things change, the more they stay the same. Like ancient Rome, modern times find us trying to keep pace with a growing population in ways that don’t tax our natural resources.

Every modern convenience brings certain downsides, including water contamination from the fertilizers that help our crops grow, oil and fuel from our cars infiltrating groundwater, and massive rainwater runoff flooding streets and driveways. The design and mechanics of permeable pavers are an attempt to address these issues in a way that stays practical and functional.

Benefits of Permeable Pavers

PICP provides certain benefits when used in South Carolina paving projects. These pavers are sustainable. They contribute toward LEED NC-2009 and LID credits by capturing and treating the contaminant load of rainwater. They require less infrastructure (like stormwater retention ponds). Furthermore, they reduce pollution and the heat island effect.

Permeable Paver Applications

When you think of pavers, you may think of a driveway or walkway. However, when the right materials and installation are used, permeable pavers prove to be remarkably adaptable. Not only can they handle pedestrian traffic and parked cars, but they’re also suitable for shopping plazas, parks, and even roads that carry a high volume of vehicular traffic.

Permeable Pavers from Unit Paving

In addition to the choice of PICP, the choice of your paving contractor matters. Using Unit Paving comes with a number of built-in advantages, including our many years of experience serving the needs of businesses, homes, and municipalities in the Carolinas, our diverse range of projects that includes courtyards, driveways, and pool decks, a wide choice of materials, and our certifications (we are ICPI Certified Installers and Green Advantage Environmental hardscape installers). Contact us to consult on your project — no matter how large or small — today.