Caution
Dips, ruts or a single sunken area have appeared in the blocks, usually where the car sits or where a trench was once dug.
Slabs tip or knock when you step on the corner, and some have started to lift clear of the bed beneath them.
Low risk
The mortar between the slabs has gone soft and sandy and can be raked out with a finger, leaving open joints.
Grass, moss and weeds keep coming back in the joints between blocks or slabs, however often you pull them out.
A green or black film has built up on the paving and the surface is treacherous whenever it rains.
Loose stones are coming away from the resin surface, and there are bald patches where the aggregate has gone entirely.
The tarmac has cracked, gone crumbly at the edges, or softened and rutted where the car stands.
The outer rows of blocks have crept outwards, the joints have opened up, and the pattern no longer lines up.
Water lies on the drive for hours after rain, or runs towards the garage and the house instead of away from them.
A patchy white bloom has appeared on paving laid only weeks ago, and it looks worse after rain than in dry weather.
Describe the job and get a fixed price from a local driveway and patio installer.