after the Pigeon Health topic with Walter Boswell "novice asks old hand" I was looking for some guidance about the loft ? I have a standard type loft ,plastic sputniks on the doors , vent grills at bottom , Perspex windows etc . looking for ideas on improving ventilation especially . how do you treat & maintain the loft ? cleaning ,when , how important is cleanliness .any tips on getting heat or natural light in ? looking forward to Walters reply