They grumble and cluck but nothing too bad. Never had any complaints. The noise is actually quite nice.
Shed sounds ideal. How many are you thinking of getting? Three hens gets me about 15-20 eggs a week which is too many for me! I sell them in work for £1 a box.
Are you buying new chickens or getting ex-battery hens?
I got mine from Brish Hen Welfare Trust. www.bhwt.org.uk
Please consider giving some of these hens a future!