Resin bound vs resin bonded: what is the difference?
By Terry O'Reilly, owner, 17 years on the tools. Updated . 4 min read.
Resin bound is stone and resin mixed together and trowelled by hand into a smooth, permeable layer over a solid base; it is what a proper resin driveway means. Resin bonded is a thin coat of resin with loose stone scattered on top; it looks like gravel, sheds stone, does not drain, and is the one that goes wrong. Terry only lays resin bound.
What is resin bound?
Resin bound is dried stone and clear resin mixed together in a forced-action mixer, then spread and trowelled by hand over a solid base at a depth of about 15mm to 18mm for a drive. Every stone is coated, so the finished surface is smooth, firm and slightly open, like a very fine gravel that has been glued into one sheet. Rain drains straight through it into the base below.
That is what we lay on our resin bound driveways. It takes two days on site, you can usually park on it about 48 hours after we finish, and it lasts 15 to 20 years with a sweep and a rinse.
What is resin bonded?
Resin bonded is a thin coat of resin painted or rolled onto the existing surface, with loose dry stone scattered over the top and left to stick. Once it has cured, the loose stone is brushed off. The finished depth is a few millimetres, about the thickness of one stone.
It looks like gravel, and for the first few months it looks good. It is quick and it is cheaper, because there is far less stone and resin in it and no base work. That is exactly why it gets sold to people who were searching for a resin drive.
How can I tell the difference by looking?
| Compared | Resin bound | Resin bonded |
|---|---|---|
| How it is laid | Stone and resin mixed, trowelled by hand | Resin coat, stone scattered on top |
| Depth | 15mm to 18mm | A single layer of stone |
| Feel underfoot | Smooth, like fine sandpaper | Rough, like gravel that is stuck down |
| Rain | Drains through | Sits on top and runs off |
| Loose stone | None | Sheds stone from day one |
| Lifespan | 15 to 20 years | A few years before it looks tired |
| Cost | Higher | Lower |
The quickest test is to run your hand over it. Resin bound feels smooth and even. Resin bonded feels like gravel and leaves stone on your palm.
Would you rather just ask Terry?
A photo and a question on WhatsApp gets a straight answer, usually the same day.
Why does resin bonded go wrong?
Three reasons, and I see all of them when people ring about a drive somebody else laid.
- Only the bottom of each stone is stuck. Tyres turning on the spot pull the top stones off. Within a year there are bald patches where the car turns and a pile of loose stone by the front door.
- It is not permeable. Water sits on the resin coat and runs to the lowest point. Under planning rules, a new drive over five square metres that drains to the road needs permission, and a bonded surface can fail that test where a bound one passes. Our planning permission guide covers it.
- It is only as good as what it is stuck to. Bonded goes straight onto old concrete or tarmac. If that surface cracks, moves or lifts, the resin goes with it. There is no base work because the whole point is to avoid base work.
Some of the worst quotes I hear about are a bonded drive sold as "resin" at a bound price. If a quote for a resin drive is much lower than the others, ask which one it is and what depth it is laid at.
Can resin bound go wrong too?
Yes, if the base under it is bad. Resin bound is a surface, not a structure. It needs a sound, solid base: either existing concrete or tarmac that is not cracked or moving, or a new base of 200mm to 250mm of compacted stone with a tarmac or concrete layer on top. Trowel it over a soft or cracked base and it cracks along the same lines within a winter.
It can also go wrong if it is mixed in the rain or laid too thin to save material. Both are the reasons resin has a mixed name in Milton Keynes, and neither is the fault of the material.
What does Terry use?
Resin bound only, with a UV-stable resin so it does not yellow in the sun, mixed on site in a forced-action mixer and trowelled by hand at a depth that suits a car, over a base I have checked myself. If your old drive is sound, we go over it. If it is not, it comes out and a new base goes in, and I say so on the visit rather than on the last day.
We lay it across Milton Keynes, on the newer estates around Shenley where the clean modern look suits the houses, and on older fronts in Newport Pagnell where a warm stone colour sits well with brick. What a resin drive costs and why a bad base is a false economy is in our resin cost guide, and finished drives are on our work page.
