Roof Ridge Venting - When in 2012 did roof venting become required instead of standard roofing codes?
Each state “adopts” the new Building Code after it has been reviewed, changes made, and approved by the State Building Codes Office. Adoption occurs on October 1, (start of the new fiscal year/budget,) with amendments adopted throughout the year. 

Little known fact is that the Code is divided into two parts: 1) construction, additions, etc., and 2) maintenance. 

You don’t need a Permit for “maintenance”, (I.e.: painting, carpet replacement, etc.) Re-roofing is often placed in the “maintenance” category. Each jurisdiction makes their own determination regarding re-roofing. 

However, roofing (initial installation) is usually in the construction category and needs a permit.