Description:Add on to existing deck at back of house; adding 15' x 15' deck, 5 steps then 12' x 15' deck. note: girder/band boards - the 2006 irc code states under section r606.14 beans are required to have support that is a minimum of 3". the support posts will need to be notched in order to accommodate the support of the beams, from that point they can be bolted to the posts. no subcontractors on permit. project # 20130029.