Girder Roof Structure

The top ends of the rafters often meet at a ridge beam but may butt directly to another rafter to form a pair of rafters called a couple.

Girder roof structure.

A girder truss is designed to support other secondary roof supports. A truss is a roof or floor support structure built from a connected series of box or triangle shaped elements to distribute load to a building s walls or foundation. It can bear the load extra loads imposed on it. It is the main horizontal support of a structure which supports smaller beams.

Here s a look at the fundamental differences between these two elements. A girder ˈɡɜːrdər is a support beam used in construction. Construction of a rafter roof a simple rafter roof consists of rafters that the rafter foot rest on horizontal wall plates on top of each wall. Their is no notching permitted in the center third of any beam.

Girders are the main horizontal supports of a structure and support smaller beams. All girders are beams but not all beams are girders. Notches on the outer thirds must not exceed 1 6 of the width of the board. Girders often have an i beam cross section composed of two load bearing flanges separated by a stabilizing web but may also have a box shape z shape or other forms.

Buildings constructed in l or t shapes use girder truss systems where the roof changes direction. Understanding how a girder is different from a beam is a necessary skill for any builder engineer or constructionworker. Both headers and girders are beams that are oriented horizontally and transfer load down to walls piers or posts.