Permeable Pavers: How They Work and Where They Suit
Most of a permeable paver is solid concrete or clay. The rain goes down the gravel joints between units, which works in the right spot. A poured surface has no joints and drains through every square metre.
What happens to rain on permeable pavers
Tip a bucket on a permeable paver and watch where the water goes. It runs off the face of the unit, which is usually solid concrete or clay, and into the nearest joint. The units carry the load; the joints do the draining. Those joints are laid wider than on an ordinary patio and filled with fine gravel in place of sand, so the water drops through into a stone base and waits there until the ground underneath takes it.
Where they're the right call
A cracked paver can be lifted out by hand on a Saturday morning and a new one tapped in, which is the best argument for them. On heritage work the laid pattern is the point, and a courtyard off the laundry can be too small to justify ordering a concrete truck.
What a driveway does to the joints
Tyres turning on the spot are hard on joints. Over a wet winter of daily reversing, the gravel fill gets carried off and silt packs into what's left, so the joints need topping up if they're going to keep draining.
Then the units start to rock or settle, and once one edge lets go it spreads. A paver sitting proud catches every wheel, the car's and the wheelie bin's. Weeds and ants move into the open joints.
What we pour instead
We've put down more than 100,000 m² of Permcon. The slab itself is 20 to 25 per cent voids, so rain goes straight through the surface at 8,000 to 10,000 mm per hour. A permeable concrete driveway is usually 125 mm thick at 25+ MPa, in plain grey, charcoal, soapstone or sandstone. Council decides whether it counts toward your permeable area, and we design to their call.
The side-by-side of pavers and a pour covers drainage, upkeep, looks and cost. For grids and gravel, see permeable paving.
Permeable pavers questions
What will permeable pavers cost me?+
Start with the base, because that's usually where the money is. The pavers are a smaller part of the bill than people expect; the stone depth your soil needs, the edging, getting a machine in past the side fence and whatever has to be broken out first all move the figure more. Compare every quote as a whole installed job. We'll price a poured surface the same way after a site visit.
Are permeable pavers strong enough for cars?+
Yes, if the units and base are built for vehicles, and the supplier will tell you whether that particular paver is. Where they give trouble is the joints on the turn, covered in the driveway section above.
Do permeable pavers sit on a special base?+
Yes, and it's the same kind a poured permeable surface needs: clean, open stone that can hold a storm, in place of the compacted fine material under ordinary pavers. Under Permcon, every 100 mm of clean screenings holds 28 litres a square metre at 85 per cent design capacity. If the ground below is slow to take water, we add an under-drain and geotextile filter cloth. It's also where quotes differ most.
Before you order pallets, get a poured figure
Ring us and an estimator comes out to walk the site. We look at the ground, the fall, access for the truck and what the slab will have to carry, then price a surface without a single joint. Have your paver quote handy so the two finished jobs sit side by side.
Check if permeable concrete suits your site
A few quick questions about your site. You get a straight answer about whether permeable concrete is the right call, including when it isn't, before anyone asks for your details.
What are you surfacing?
Tell us about your project
Tell us where the site is and what you're planning. An estimator from your state team will call you back, look at the site with you and give you a real figure, from a single driveway to a council car park.
No joints, poured in one piece
