Renewal work is usually more drastic than repair and has a high visual impact, so it is important to be sure that there isn’t a more limited intervention that would also be effective.
Mae gwaith adnewyddu fel rheol yn fwy eithafol na gwaith atgyweirio ac mae’n cael effaith sylweddol ar yr hyn sy’n weladwy, felly dylech ystyried a oes modd ymyrryd yr un mor effeithiol ar lefel lai.