crosstimber

Crosstimber is a term used in timber framing to describe horizontal or diagonal timber members that cross within a traditional frame to provide stability and load distribution. In this sense a cross-timber acts as a bracing member or tie that links vertical posts, helping resist lateral racking and transferring roof and floor loads to the foundation. Cross-timbers are usually cut from local timbers and set where floors, ceilings, or roofs require lateral restraint. Joints are typically pegged mortise-and-tenon or lap joints, though later restorations may use nails, bolts, or metal fasteners.

In typical construction, cross-timbers appear as ties at the top of bays, floor or ceiling framing members, or diagonal bracing that stiffens the wall frame. In regions with half-timbered or wattle-and-daub construction, the cross-timber grid forms both the structural skeleton and the exterior or interior decorative pattern.

Historically, cross-timbering is found in medieval and early modern timber-framed buildings across parts of Europe and North America, especially in areas that used timber frames with infill panels. The exact terminology varies by region; some builders refer to these members as tie beams, girts, braces, or crown posts, depending on their function in the frame.

Today, crosstimber remains a term of reference in restoration and historical study, while modern timber framing may replace traditional joinery with metal fasteners or engineered wood products.