R602.7

Section R602.7 is titled 'Headers' and covers the requirements for header spans. A cross-reference to 3 tables in this code which list allowable header spans is established. The purpose of this section is to prevent structural failure.

The model shows 2 exterior bearing wall headers. The 1st is a double 2x10 spanning 5'-11" with floor joists bearing on and attached directly to the header. The 2nd header is also double 2x10s, but only spans 70% the distance of the 1st header, in accordance with footnote f of table R602.7(1), since the top of the header is not laterally braced. Presuming the headers are the maximum span allowed per the table, what is the ground snow load and building width of the dwelling?