160 m2 by 100 mm thick come out at 16 m3 around £100 a cubic metre £1,600 but really is something you don't want to do
I was gonna say my math's must be way off I have had drive way quotes of concrete roughly 6 metres by 5 for just over 1K (parts and labor) I could probably put roughly 5-6 of them in my entire back garden giving me roughly 6-7K which includes the whole lot of building/labor. I think ill get some quotes in since its tricky to get building material cost and labor right.
What do you feel is the best solution for a back garden ? Just trying to come up with ideas. (to answer your question; old patio is crumbled/broken/cracked and no good, basically my garden is worn out) To give an idea of what I hoped for is similar to these: Something like this: https://goo.gl/images/XUCZGw or https://goo.gl/images/GGBiuW patio either concrete or slabs at front, middle grass, back either concrete or slabs and on top a shed for storage.
Really too fancy for myself, my budgets roughly 6K which is why I was looking to keep it as simple and cheap as possible ie concrete or patio slab the whole lot or leave a patch in the middle for soil/grass, I could put artificial grass down the road.
If you have a large area that you don't want to maintain. I would go with a combination of some decking, slate chippings for a border and artificial grass in the centre. Need to get someone to come in and level everything with a machine and then put down some geotextile, stone base and then cover with artificial grass. slate on the borders will make a good contrast with the grass and deter cats. Easily changed if you get bored or sell up
Thanks for all the replies, yes some good ideas not sure about the decking although it does look nice a few neighbors said they hated it and it didn't work well for them they stuck with concrete/slab patios in end. I could probably do the slate chippings borders even the artificial grass myself, but I like the idea of putting cats out the garden too.