How Long Does a Tarmac Driveway Last in Ireland?
A properly installed tarmac driveway in Ireland should last 20–30 years. We've relaid driveways in Dublin that were installed 25 years ago and were still fundamentally sound. We've also resurfaced driveways that failed within 5 years of installation. The gap is almost always the sub-base.
What Actually Determines Longevity
1. The sub-base
This is the foundation beneath the tarmac — a layer of compacted MOT Type 1 crushed stone that distributes load and prevents the tarmac from cracking or sinking. On good, stable ground, a 150mm sub-base is typical. On softer ground, 200mm or more.
A tarmac surface on a poor sub-base will fail. The tarmac itself is flexible and will bend with ground movement, but if the ground moves too much — soft spots, waterlogged areas, inadequately compacted fill — the tarmac cracks and eventually breaks apart. No amount of good quality tarmac compensates for a bad base.
2. Drainage
Standing water is a long-term enemy of tarmac. Water that sits on the surface and works its way into the sub-base gradually softens it. In winter, water in the sub-base freezes, expands, and pushes up through the tarmac. A driveway that drains properly — graded away from the house, with no low spots — lasts significantly longer than one with ponding.
3. Edge support
Tarmac without edge restraints frays at the edges over time. The tarmac needs a kerb, edging block, or channel drain at the boundary to contain it. Without this, the edge begins to break away and the failure progresses inward from there.
4. The tarmac specification
Not all tarmac is equal. The standard specification for a residential driveway wearing course is AC10 (10mm aggregate, dense graded, bitumen-bound). Using the wrong grade, or using recycled material on a residential job, produces a surface that won't perform as well or as long.
5. Load
A driveway that carries standard cars will last longer than one that regularly takes a heavy van or trailer. Tarmac can accommodate moderate heavy vehicles without issue if the sub-base is adequate, but consistent heavy axle loads accelerate wear.
Signs Your Tarmac Is Reaching End of Life
- Edge fraying: The edges break away, progressing inward.
- Cracking: Particularly if the cracks follow a pattern (drainage channels, utility routes beneath the surface, soft spots in the sub-base).
- Potholing: Surface material breaking away, usually where water has worked into the structure.
- Surface oxidation: The surface looks grey and dry rather than dark — this is cosmetic and can be addressed with a seal coat.
- Sinking or uneven areas: The sub-base is settling or has failed in a localised area.
When to Repair vs Replace
Repair makes sense when:
- The sub-base is fundamentally sound
- Damage is localised — edge fraying, individual potholes, or cracking in a small area
- A seal coat can address surface oxidation
Replacement makes sense when:
- Cracking or sinking is widespread
- The sub-base has failed across significant areas
- The driveway is more than 20–25 years old and has multiple issues
We'll always give you an honest assessment at the site survey. If the existing tarmac can be repaired or resurfaced at less cost than replacement, we'll say so.