Light wooden ladder with perforated risers - uses riser bracing as rung fixing between parallel laminated runners

摘要

Each riser is made of two or more parallel runners (1,2) connected at equidistance heights by bracing (4) to give the strength of a solid riser but at much less weight and cost. The runners are made of glued laminate wood and a central longitudinal hole is made in the laminate before gluing to take a steel reinforcing rod. The cross bracing has holes (5) to take the ladder rungs (7), the fixing can be either glued or dowel pins (8) can pass through holes in the bracing and through the rungs.