Building Permit Information, Applications and Fees A building permit is a municipal document from the City of Sarnia that provides legal authorization to begin construction of a building project. Learn More Residential Fences A building permit is not required to construct a new fence. However, the City does have a by-law in place […] Learn More Swimming Pools A permit is required to construct or install a pool or any other structure located outdoors which is capable of […] Learn More Sheds and Detached Garages Any accessory building (such as a shed or a garage) over 10 square metres (108 square feet) in size will […] Learn More Decks A building permit is required for a deck higher than 0.6 metres (2 feet) above average ground level or any […] Learn More