Too hot for fleece?

Ka

So we have a Halo sleep sack but its a fleece one. I want to try it tonight because my boy keeps busting out of his swaddles but he likes to have something more than just a sleeper on. Its very hot where I live, in the 90s but we keep our house very cool. I keep my AC going all night and our fan on full blast. Is anyone else using a fleece sleep sack? Should I just have him wear a diaper in it?