Perch question?

Putting the finishing touches to the coop and I would like to know about perching and perches. My coop is 4 x 4 ft and 3ft 6 high at the back I've thought about putting a bank of perches towards the back, if that's ok how far apart should they be and should they all be the same hight or on a slope lower at the front and higher towards the back. Also what hight should I start and finish at?

Anything up to 2 feet high or slightly higher will be fine. Try to have the perches higher than the bottom of the nest box entrance to discourage them perching there.