can you lay new turf on top of your old lawn?

The new turf roots would not be able to get down into the soil. he best idea is to cover the area with black plastic for a couple of months to kill off teh old grass ( and weeds!) then loosen the soil with a fork then put down new turves. By that time it will be late summer and the new turf can settle in over autumn when there should be more rain so you won't have to water it so much. Or you could use a lawn weedkiller to get rid of weeds then spread some clean soil or compost and re-sow with a grass mixture suitable for your site ( shady, hardwearing etc).

But you'll get much better results if you remove the existing turf, fork it up, level, compress and relevel, throw growmore down, then lay turf!

Phew! I'm tired just thinking of all that work!

I know what you mean, I've done it many times, hate it, but it's worth it in the end. Thank god I'm too old to do that again for other people ...