Best way to tidy areas outside of lawn, stop unwanted growth?

We have various trees, which surround the lawn, and in between these are areas full of unwanted shrubs and weeds. They have been persistent and a couple of gardeners we have spent a lot of money on have not been able to find a permanent cure to the growth of these unwanted plants. 

The objective: To completely cover these areas in 'wood chip' or equivalent, over a layer of 'thick fibre cloth' or equivalent, to suppress and stop these growths permanently, once and for all. 
So we will end up with a piece of square grass lawn, surrounded by woodchip (or whatever you call it), trees, and nothing else.

Ive quoted myself, because I dont know what the actual terms are, or what the materials are actually called.

can anyone lead me down the right path? and can anyone recommend any suppliers? Theres quite large areas to cover so Im guessing we would need tonnes.

thanks

You need a weed suppressing membrane- you must must secure it properly-then bark chippings laid on top -probably at least 2 inches deep

You can buy these in bags from any garden centre-it can work out quite expensive if you are going to need lots-there may be a supplier near you that can provide a bulk unbagged -check that out

The downside to all this is that the birds will flick this stuff all over the place -and it won't stop the odd weed germinating in the chippings themselves-but if you can put up with that......

If you don't want to use bark,  you could try gravel (or slate chippings) instead.  Geofff's quite right when he says the birds will flick bark chippings all over the place.  I have used gravel on top of a black water-permeable membrane with great success.  It covers part of the area at the back of the house because I didn't want to have the whole of it paved.  I planted some stuff through it before putting the gravel down - 20 years later it still looks fine & there are no weeds at all.

fiohaa,

You make it sound as if an awful lot of material is needed. How many square metres are we talking about? A local tree surgeon could probably supply you with bulk quantities of chipped wood.

Joe