The short answer
Resin-bound driveways are permeable: water passes through the voids between the encapsulated aggregate particles into the base and sub-base below. Resin-bonded surfaces are not genuinely permeable. This distinction determines whether a front driveway in England qualifies as permitted development under the 2008 SUDS rules. See resin-bound vs resin-bonded and planning permission for resin driveways for the full context.
Permeability is one of the headline selling points of resin driveways — but not all resin surfaces are equal in this respect. The word “resin” covers two very different products, and only one of them actually drains rainwater through its surface. Understanding which type is which — and verifying that your specific installation is genuinely draining — is important both for planning compliance and for long-term drainage performance.
Resin driveway permeability at a glance
- Resin-bound permeability Yes — drains through aggregate voids
- Resin-bonded permeability No — water runs off the surface
- SUDS compliance Resin-bound qualifies; bonded generally does not
- Typical drainage rate 600–900 litres per m² per hour (resin-bound)
- Maintenance of permeability Annual light cleaning prevents void blockage
- Planning consequence Bound = usually no permission; bonded may need permission
How resin-bound achieves permeability
In a resin-bound surface, every aggregate particle is pre-coated with resin in a forced-action mixer. When the blend is trowelled onto the base it sets into a matrix of stone particles bonded at their contact points, with consistent interstitial voids between them. These voids form a three-dimensional drainage network through the full 15–18 mm depth of the surface. Rainwater enters the voids, percolates down through the matrix and enters the base beneath — typically a 40–100 mm layer of open-graded macadam that retains water temporarily before it percolates into the sub-base and eventually the ground. Permeable resin-bound surfaces installed to CIRIA guidance typically achieve drainage rates of 600–900 litres per m² per hour, far above the level needed to handle normal UK rainfall events.
Why resin-bonded is not truly permeable
Resin-bonded surfaces work differently: the resin is applied to the base first, then aggregate is scattered over the top and pressed in. Only the undersides of the stone particles are coated; the spaces between them are not part of a controlled drainage matrix. Water falling on a resin-bonded surface runs across it rather than through it, creating run-off in the same way as concrete or tarmac. This is why resin-bonded does not satisfy the 2008 Government requirement for a permeable front driveway, and why it may need planning permission. It is also less durable and shorter-lived. The difference matters so much that every resin driveway specification should confirm in writing which product is being used — see how to choose a resin driveway installer.
| Property | Resin-bound | Resin-bonded |
|---|---|---|
| Rainwater drainage | Through the surface | Off the surface (run-off) |
| Drainage rate | 600–900 L/m²/hr typical | Negligible |
| SUDS compliant | Yes | No |
| Planning (front drive England) | Usually permitted development | May need permission |
| Flood-risk contribution | Minimal — absorbs local rain | Same as impermeable hard standing |
How to maintain permeability over time
The voids in a resin-bound surface can gradually become partially blocked by fine silt, leaf debris and organic material deposited by rain or blown by wind. Annual light pressure-washing and regular sweeping of autumn leaves prevents progressive void blockage and maintains drainage performance. Full blockage of a resin-bound surface is unusual when routine maintenance is carried out, but a surface that has been neglected for many years and is visibly ponding water may benefit from a specialist jet-vacuum clean that clears the voids without damaging the aggregate. This is general information, not professional advice; drainage performance varies with the base design, installation quality and maintenance history of your specific driveway.
Make sure your resin driveway drains properly
Ask local installers to confirm in writing that the system they are specifying is resin-bound (pre-mixed, permeable) and that the base design supports drainage to the subsoil or a soakaway.
Frequently asked questions
How do I know if my resin driveway is permeable?
Pour a small amount of water on the surface. Resin-bound will visibly absorb it within a few seconds; resin-bonded will cause it to run off. You can also ask your installer for the product data sheet confirming the drainage rate.
Can a resin driveway get blocked over time?
Yes, voids can clog with fine silt and organic debris over years of neglect. Annual sweeping and pressure-washing maintains drainage performance and prevents progressive blockage.
Is resin better than block paving for drainage?
Both can be permeable when specified correctly. Resin-bound is a single poured matrix with no joints to weed or shift; permeable block paving has open joints filled with aggregate. Both satisfy SUDS rules. See resin vs block paving.
Does a permeable driveway need a soakaway?
Not necessarily. Ideally, the sub-base retains water temporarily and it percolates into the ground. Where ground permeability is very low (clay soils), drainage to a soakaway, garden area or storm drain may be needed.
Sources & further reading
- CIRIA — SUDS manual, permeable paving design, drainage rates and void maintenance
- GOV.UK — Planning guidance on householder driveways and the 2008 SUDS permeability rules
- Pavingexpert — technical guidance on permeable paving drainage and void maintenance
- Environment Agency — surface water drainage guidance and SuDS principles for householders
This is general information, not a site-specific survey, quote or professional advice. Prices, timescales and outcomes vary with your ground conditions, drainage and chosen installer. Always obtain a written quote and check the installer before committing.