In response to our need for new flexible seating in our Lab theatre, I developed a less expensive alternative for seating risers. My system cost a third of the price of commercial riser systems and can be repaired/replaced by even moderately skilled carpenters. Like traditional parallels in all other respects, this design features an all-plywood support system which, though heavier than its lumber counterpart, can be built more quickly and easily by running a flush-trim router bit around a lauan template. Keeping such a template also simplifies making replacement parts.

FIGURE 1: 9″ PLYWOOD PARALLEL COMPONENTS