R1003.4.1

Section R1003.4.1 is titled 'Seismic anchorage' and covers the requirements for masonry chimney to building connection details in seismic design category D locations. The number, size, embedment depth, reinforcement bar connection method, and building connection method of strapping is established. The purpose of this section is to prevent structural failure of the chimney during an earthquake.

The model shows a partial section of a masonry chimney connected to the floor assembly of a dwelling. Notice that the floor joists have been notched to recess the strap and lag bolt heads, so that the floor sheathing will lay flat. Blocking is installed between the floor joists to add strength to that portion of the floor assembly which provides better support for the chimney.