I should have added to my first post that we have both here.

Our first kennel has a concrete base which was laid by a professional builder about 6 years ago. It is dug in, lined, supported, meshed etc etc.
Our 2nd kennel sits on slabs, laid by a handy man and his accomplice, both sloping to assist drainage.
The concrete has deteriorated over time with small stones coming loose with the pressure washer and cracks appearing.
The slabs have been down for 3 years and are still immaculate, they come up perfectly with the pressure washer and look and smell cleaner than the concrete.
If we moved house tomorrow it would be slab that were going down in the new run.
My dogs only ever dig in the forest, although I might nip up to Catherine's and let them have a go in her kitchen...
