But some said it is 100 sq. Today because of all the porch collapses they are making her replace the porch not just repair and bring it up to todays code. 4 Valuable Ideas Simple Small Shed Plans Barn Style Garden Shed Plans Barn Shed House Plans Shed Building Home Depot Plans For A Garden Shed What im trying to build a shed in the backyard without the need for permit. How to build a shed without a permit . Especially if the building may somehow cause changes that may affect their lives like block the view or causing too much shade etc. However the inclusion of electricity plumbing the placement and its purpose could need a permit. So I would suggest a meeting with the city or towns local urban planning department and they will guide you thru it. There are many things to consider before determining if one is needed for yours. According to the 2002 Los Angeles County Building Code Section 1063 a building permit shall not be required for one-story detached accessory building