Kennel size and location.

[ellir0305 9]

We are looking to get a pup soon once we've got a kennel / run sorted. The most secure location we have is against a south facing block wall so I am conscious of the heat in the summer. I am thinking that if I build it with the sleeping area against the existing wall and  the long open side facing west that will be my best bet as it will only get direct afternoon/evening sun. I have only built one set up before at 9 x 5' which was ok. Is there an optimal size or layout that works best? Going to lay a concrete slab with a channel drain, probably a single course of block then wood frame with galv panel on the open side. The dog will be a spaniel or spaniel x most likely for size reference. Any advice is greatly appreciated.