Patio laid without a fall
Every patio should slope gently away from the house so rain runs off rather than sitting on the surface. The right fall depends on the paving and site, so it should be set for the individual job. A patio laid dead level, or worse, sloping back towards the walls, will hold water across its whole width after every shower, leaving green staining and slippery slabs.
There is no surface treatment that fixes a missing fall. The slabs have to come up and go back down on a corrected bed.
Puddles in one spot
A puddle in the same place every time usually means part of the base has settled. That happens where the sub-base was too thin, was not compacted, or sat over soft ground or an old trench. If it is one or two slabs, they can be lifted, the bed rebuilt and the slabs relaid and repointed. If several areas are dipping, the base under the whole patio is suspect.
Patio drainage problems on clay ground
Clay holds water. Even a well laid patio with a good fall can struggle if it sheds water onto a lawn or border that is already saturated, because the water backs up at the edge. Many gardens around Southampton have clay under a layer of gravel or brickearth, so this is something we check on a first visit.
The fix is giving the water a route: a channel drain along the low edge, or a soakaway where the ground allows it, so water is carried away rather than left sitting against the paving.
Patios
- Natural stone and porcelain options
- Careful levels and drainage
- Neat edges and lasting foundations
Fixes, from smallest to largest
- Lift and relay individual sunken slabs on a new bed
- Repoint failed joints so water cannot wash out the bedding
- Add a channel drain along the low edge or by the house
- Relay the whole patio with a proper fall on a rebuilt base
Water near the house
If water pools against the house wall, deal with it sooner rather than later. Patios should also sit below the damp proof course. Running a drainage channel along the back wall to stop water tracking towards the door is a job we have done on Southampton gardens, and on our figures extra groundwork such as a channel starts from around £400 when it is part of a patio job.