He looks like a Sabino, chestnut based. To be sure I'll ask if his face is roaned also? True roans have solid heads. By that I mean the colored part does not roan out. Also a true roan will change as they shed. My bay roan is very bay looking in winter, sheds nearly white then is a rich roany mix in summer. But her face is brown(bay). I had a chestnut/sorrel sabino that looked a lot like your horse in coloring.. Sabino is a pattern where the white markings are jagged. Not all sabino patterned coats are roaned. I think all or most of the Clydsdales are Sabino. High jagged white legs, usually dark coat on top with maybe splashes of white underneath on the belly. Normally a lot of white on the face, bald is common, white muzzle continueing to the bottom lip/chin..
He's pretty, btw.