What Is the Difference Between Porosity and Perviousness?

Amanda Delatorre • September 7, 2023

Understanding the differences between environmental terms is key for community projects. Before installing permeable pavement, you should know the difference between “porosity” and “perviousness.” While they sound similar, they have different meanings. We will explain the difference between porosity and perviousness and explore how they impact community projects.

What Is Porosity?

Porosity refers to the empty space or voids in a material or surface. It is a measure of the ability of a material to absorb and hold water. Porous materials include soil, rocks, and even pavement. When it rains, porous surfaces absorb the water and filter it into the ground, reducing runoff and erosion. Porosity is important in landscaping projects, as it helps with water conservation and drainage.

What Is Perviousness?

Perviousness refers to the ability of a material to allow fluids to pass through. Pervious surfaces include porous pavement and asphalt. Unlike regular pavement, which is impermeable and creates water runoff, pervious pavement allows rainwater to filter through the surface and into the ground. Community project leaders should consider pervious surfaces in order to reduce stormwater runoff and sustain the local infrastructure.

The Core Differences

One key difference between porosity and perviousness is the materials they apply to. Porosity relates to soil and rocks, while perviousness describes manufactured surfaces. While porosity alludes to the space within a material, perviousness allows liquids to drain through a surface’s inner channels.

Porosity and perviousness play an important role in many community projects, including green infrastructure. To reduce stormwater runoff and improve water quality, many cities are designing green infrastructure that incorporates porosity and perviousness. These projects include rain gardens, bioswales, green roofs, and permeable walkways to absorb rainwater.

The differences between porosity and perviousness are important to understand for anyone interested in improving their community. At Rockpave, we want to help you access premium permeable gravel and understand what you need to make it work for you. We provide top-of-the-line resin bound paving that can maximize drainage, reduce flooding, and make maintenance easier for infrastructure. Reach out to us today to learn more about porosity and perviousness and how they relate to permeable pavement solutions.

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Resin Bound Tree Pit Surrounds

By Jim Robinson • September 9, 2025

Resin Bound Tree Pits: The Smarter Way to Protect and Showcase Urban Trees In towns and cities everywhere, urban planners face the same challenge: how to protect tree roots while keeping public spaces clean, attractive, and safe. Traditional solutions—like loose gravel, soil, or metal grilles—often fall short. That’s where resin bound tree pits come in. What is a Resin Bound Tree Pit? A resin bound tree pit is a surfacing system that uses a blend of natural stone aggregates bound together with a clear, UV tolerant resin. Installed around the base of a tree, it creates a strong, permeable, and decorative surface that allows rainwater to drain through while protecting the soil and roots below. Think of it as a breathable shield for urban trees: tough enough to withstand foot traffic, but porous enough to support healthy root growth. Why Choose Resin Bound for Tree Pits? Permeability for Healthy Trees The resin bound surface is fully porous, meaning water and air can still reach the roots. This promotes long-term tree health and reduces the risk of waterlogging. Cleaner, Safer Surfaces Unlike loose gravel, resin bound surfaces don’t scatter, sink, or create trip hazards. In fact they help to eliminate trip hazards! They provide a smooth, stable finish—ideal for high-footfall areas. Aesthetic Appeal With a wide choice of natural stone colors, resin bound tree pits can complement surrounding paving, creating a polished, modern look in public spaces. Durability & Low Maintenance Resin bound surfacing is resistant to weeds, litter build-up, and erosion. It keeps the area around tree bases tidy without constant upkeep. Accessibility Friendly A smooth surface around tree pits is easier to navigate for strollers, wheelchairs, and pedestrians—making public spaces more inclusive. Where Are Resin Bound Tree Pits Used? City sidewalks to reduce tripping hazards and improve walkability Parks and plazas for cleaner, more attractive landscapes Shopping districts where appearance and safety matter Corporate campuses or schools to combine functionality with visual appeal A Sustainable Choice for Urban Environments! Resin bound systems align with modern sustainability goals. By ensuring stormwater naturally drains into the ground, they help prevent flooding and reduce strain on drainage systems. Combined with their long service life, a very competitive price point, they’re a future-proof investment for greener, smarter cities. Final Thoughts If you are considering the use of resin bound for your tree pits, don't just choose any resin bound product, choose one that is time tested, data driven and will sustain the demands of a harsh city environment. A good resin bound product will have similar strengths to concrete yet it will be completely pervious. Resin bound tree pits are more than just a neat landscaping detail—they’re a practical solution that supports tree health, improves safety, and enhances the look of urban spaces. If you’re planning a streetscape project, commercial landscape, or public park, resin bound surfacing could be the perfect choice for both form and function.