The planning process aims to protect the quality of the environment and to ensure new developments are well designed and in keeping with your property and the ‘street scene’ in general.
Planners will ensure your development does not affect your neighbours privacy or cause any loss of natural light.
A valid planning application requires detailed scale drawings of both the existing and proposed elevations and floor plans of the property. Location and site plans are also required.
Planning permission is not always needed but the rules are frequently changing so I would always check and obtain written confirmation from your local council before any building work starts.