Flitch Plate Installation in a Bi-Level House

Flitch Beams and Bi-Level Homes

• The term bi-level applies to homes with any of several types of two-story floorplans, including split-level ranch homes, conventional above-grade two-story homes, and homes that include two floors plus a basement. In bi-level homes, builders might use flitch beams to replace solid lumber beams, engineered wood beams or steel beams. Flitch beams function as load-bearing members for floors, walls or roofs.

Flitch Plate Headers

• In split-level or bi-level homes with attached garages, builders might use flitch plate beams to construct headers for garage door openings. Headers are framing members that span large openings in walls, such as window or door openings. Headers are wider and thicker than conventional wall studs, which allows them to safely support and distribute roof or floor loads. Although flitch plate beams are suitable for all types of headers, they are commonly reserved for large openings because of their cost and labor requirements. Builders support flitch plate beam headers at each end with posts, studs or prefabricated shear walls.

Flitch Plate Beam Girders

• Flitch plate beams are a suitable alternative to steel, engineered lumber or solid lumber beams for floor girders. Floor girders span the center of a bi-level home's lower story ceiling. The girder bears the load of floor joists at the center of the second story's floor. As floor girders, flitch plate beams run from wall to wall with intermittent support from posts or lower-story load-bearing walls. A flitch plate beam also might span a basement's ceiling to support a bi-level home's first floor.

Flitch Plate Rafters

• Builders occasionally apply flitch plate beam construction to roof frames. Flitch plate sandwiches can substitute for rafter ties. Rafter ties run between corresponding rafters in an open ceiling, thus impinging on the ceiling's open appearance. A flitch plate rafter ceiling usually doesn't require rafter ties, allowing the ceiling to expose the full height of the roof frame. Flitch plate beam rafters appear in both multilevel and single-story home construction.