My first thoughts were of any changes in your home, lifestyle that might be upsetting him. Maybe the remodeling is stressing him out, making him feel as though his space were being invaded; or it could be he's not feeling well too I know several dogs who don't like being disturbed while sleeping, but it sound like this is new to Harley. I'd probably get him to the vet's in the next day or so if it continues, just to rule out a physical cause. Have you corrected him when he growls...what was his reaction? It really is odd and I know it must be very upsetting for you too. Maybe the vet will have some ideas...I hope things improve