as a rough guide................... would i need planning permission to extend the garage at the bottome of my garden?. its about 4m by 3m and i would like to extend it to 7m by 8m. i will not be increasing it in height. it will be more than 5m away from my house. and it will not be any noticably nearer to the main highway. i will of course speak to my local council, but i just wanted some pointers thankyou
Clearly you know quite a bit about the 'rules', as you mention several of the key criteria that enable you to use Permitted Development Rights, thus avoiding the requirement to ask for PP. See here for the rest of 'rules' - just the bit about the distance to the Highway may be an issue. http://www.planningportal.gov.uk/england/genpu b/en/1106655490418.html
In my experience differrent councils have different rules. Your best bet is to phone Building Control at your local council and ask them. They are usually very helpful people.