I know that you can't build a boundary wall gate or fence at the front of your property higher than 1m as permitted development but what if you are proposing 2m high driveway gates, set back 5m from the back edge of footpath, linked to the front boundary wall by a continuation of the existing 0.8m high front boundary wall? Reason for the 2m high gates is privacy, a hedge will be planted behind he lower wall.
Will permission be needed? The local planning department charge £65 for "advice" which is a bit of a cheek....