New patio over the old one — sometimes brilliant, sometimes a disaster
Going over the top saves the dig-out and the skip. It also raises your levels by 50mm and inherits every problem the old patio has. Here's how to tell which side of that trade you're on.
Your patio
Size · 1 of 5
5 × 3 m15 m²
How big is it?
5 × 3 m15 m²Indian sandstonean old patioAnywhere in the UKStack bond
When over-the-top works
The old patio is sound, flat within 10mm, drains away from the house, and you can afford the height: 50mm of build-up still leaves you 150mm below the damp-proof course.
When it doesn't
Rocking slabs, hollow spots, or moss that never dries mean the base underneath has failed — a new layer fails with it, just slower. That's the lift-and-relay estimate in the calculator above.
The honest comparison
Run the calculator both ways: "an old patio" prices the lift-and-relay; if yours is sound concrete, "concrete" prices the over-the-top route. The difference is what the dig-out is really costing you.
Keep planning
- The full patio calculatorStart from scratch with your own numbers.Open it →
- The patio base your hot tub actually needsA filled six-person hot tub weighs about as much as a small van. Most patio bases are built for garden chairs. Here's what yours needs underneath it, and what that honestly costs.Plan this one →