Will your extension be completed by May 2019. The design will need to be carried out or reviewed by a Chartered Professional Engineer. What Size Shed Can I Build Without Planning Permission In England In 2020 Building A Shed Building A Wood Shed Wood Shed Plans Overall height must not exceed 4m dual pitched roof or 3m any other roof Maximum height of 25m if the shed is within 2m of a dwelling boundary. How big can you make a shed without planning permission . However there are often other factors at play as well. Make sure no part of the shed is within 35 metres of the border with a road to the rear of your house. This rule of thumb applies generally to single-storey sheds with a floor space of less than 30 square metres. For assistance with planning bear in mind these planning regulations. The following allowances for building a shed without a permit apply to private houses only. Before you set to work weve put together a checklist to make sure this applies to your projec...