Trimmers And Headers. In the making of stair and chimney openings it becomes necessary to support the ends of joists other than in the usual manner. This is done by cutting in headers as in Figs. 25, 26 and 27. Where the span is not great, such as at an ordinary chimney in residence work, in which but one or two tail beams are to be carried, headers are not doubled and are merely spiked in place. Where many joists are to be carried, headers or trimmers, or carrying joists must be doubled. Iron stirrups or hangers should be used instead of spikes in joining headers to carrying joists where spikes would weaken the carrying joist and would not give
Fig. 26. Placing Headers and Trimmers.
Fig. 27. Floor Frame and Rough Floor.
Headers and Trimmers in Wall Frame sufficient strength to the joint. Except upon long spans, tail beams are usually fastened to the header by spiking only. On long spans they should be framed to the header as joists are framed to a girder, a 2"x 4" being spiked firmly to the header as a support.
In determining the amount of space to allow for head room in framing about a well hole for a stair, determine the run and rise of the stair from the plan and elevation, and then plan to allow at least 6' 6", measured from the proposed nosing line of the treads up to the proposed location of the trimmer, or carrying joist, or header, as the case may be, at the ceiling level, Fig. 121.
Fig. 29. Headers and Trimmers in Wall Frame.
Second Floor. Joist.
ings forms the stool, also known as header. The illustration shows the manner of framing for openings of different widths. A small single window may require but one thickness of 2 " x 4 ". A medium sized opening will have a header of two pieces of 2" x 4". Where
Fig. 30. Stud and Joist Patterns the opening is rather large, as in the case of double door openings, two joists will be set on edge over the opening as header.