Long story short, you pull up the entire patio, stacking the bricks or pavers neatly. Dig up the sand, replace the drainage and repave. If you have plenty of help, this can be done without breaking your back; otherwise hire a professional.
We're in the middle of repairing our crazy paved patio at the moment:
- Due to being too high, it's breached the damp course on the house so the top has been removed, the top course of bricks on the supporting walls removed and the top sand/cement base removed.
- There is subsidence damage to the supporting walls due to no [proper] foundations and a leaking drainpipe soaking into the ground under the patio. The pipe will be permanently repaired and the damaged section of wall properly rebuilt.
- The patio has also been reduced in length (due to breaching problems and to reclaim so lawn) so a new retaining wall will be built across the end. Behind this a layer of hard core will be packed.
- The top will be covered with a sand/cement base onto which the crazy paving top will be replaced.
Due to a skip lorry, our brick driveway has been really mashed up and needing repair (more that it already did - it has sunk where the car wheels stand). This will involve:
- Removing the bricks
- Putting in a layer of hard core (probably digging down a bit first as I suspect original layer didn't put in enough foundations (if any) - we will find out when the bricks are lifted)
- Putting on a sand/cement base
- Putting bricks back down (in original pattern).
My warning is if you're not too sure of a builder take a careful look around for where he's tethered his horse (my mother who had the work originally done didn't spot his horse and I'm having to get it redone).
