No, this is not acceptable!

All Poundbury property owners are bound by covenants and stipulations as part of the purchasing agreement. This is to protect our close living spaces and keep the development looking smart. It is not permitted to change the external colour of any property without the permission of the Duchy of Cornwall. This of course includes changing a colour theme in a courtyard. A range of legal actions is available to the Duchy, MANCO or other owners. Some unauthorised changes will render your property unsaleable without return to original planned status. ( Please read Stipulation 1 in this website, and in your documentation)