The figure shows different types of lattice roof girders and frames constituting wooden engineering structures, which can be made of boards, logs or square timber. Mainly mechanical connectors are used to connect the elements: nails, bolts, press-in rings and plates.
Roof trusses: a) plank truss, b) log truss, c) overlays connecting the halves’ truss, d) vertical brace, c) nailed joints, f) connection details with tiles: barbed; 1,2 - upper and lower straps, 3 - post, 4 - diagonals, 5 - overlays connecting the spar chords, 6, 7 - brace planks, 8 - pressed plates made of sheet metal, 9 - spacer.
Lattice trusses made of boards (Lynx. a) can be used for single-pitched and pitched roofs. Gable trusses are often made of two segments connected by means of bolted or nailed examples. The truss shown in Fig. b is made of logs, and the individual elements are connected by pressing plates. These tiles can also be used to connect the boards in the trusses shown in Fig. d.
The trusses and girders should be installed (performed) with the use of a negative arrow (upward deflection), that after loading, the bottom flange of the spar will assume a horizontal position without visible downward deflection.