Ask any builder who has used parallel-chord floor trusses how he likes them and you're likely to get an enthusiastic answer. No wonder. As building components go, they have a lot going for them. A floor truss can span 38 feet with no intermediate support. It does this not with massive timbers, but with a series of cleverly arranged 2x4s. The use of smaller-dimension lumber to shoulder large loads means that a trussed floor makes more efficient use of wood than a floor framed with 2x8s or 2x10s. A truss makes better use of labor, too. There's no cutting, so the framing goes faster; duct runs can be built into the webs, speeding
