Roof Truss Terminology

Truss a pre built structural member capable of supporting a load over a given span.

Roof truss terminology. Pitched truss any truss in which the top chord is sloped and the bottom chord is horizontal. The terms pitch and slope are simply two different ways of expressing the same measurement. Truss terminology the terms below are typically used to describe the various parts of a metal plate connected wood truss. Truss terms the terms below are typically used to describe the various parts of a metal plate connected wood truss.

The truss profile span heel height overall height overhang and web configuration depend on the specific design conditions and will vary by application. Ansi is the american national standards institute. Trim along the edge of roofing at a gable end. Ansi tpi 1 1 1995 is a publication of the truss plate institute tpi and ansi defining a standard for design and manufacture for metal plate connected wood trusses mpcwt.

The lower portion of a piggyback truss. A gable roof has vertical planes usually on the. The same roof has a 4 12 or 1 3 pitch. Truss terminology technical terms used in the truss industry may not be familiar.

A truss may also be so manufactured because of transportation considerations e g. It is fixed to ends of battens purlins or verge rafters. Tension forces being exerted on a truss member that creates pulling apart or elongating effect. If the roof eave extends beyond the gable end wall by more than 1 then a dropped gable is normally used.

A roof s slope is the number of inches it rises for every 12 inches of horizontal run a roof with a 4 in 12 slope rises 4 inches for every 12 inches of horizontal run. Roof trusses manufacturers terminology components of a truss apex peak. Some of the more common are listed below and are illustrated on pages 3 4. Bottom chord bc or tie beam.

Anchorage is the connection of the roof or floor truss to the building structure. The truss profi le span heel height overall height overhang. The highest point on a truss. The gable roof provides for the most basic of roof systems.

A triangulated combination of members and joints that forms a rigid structural component of a roof designed to support both permanent and imposed loads. Bearing cut or seat cut. Flat truss a truss which has the top chord parallel to the bottom chord over the entire length of the truss. The part of a structural member that extends beyond its support see figure.

Slopes at roof pitch. Square the amount of roofing material needed to cover 100 square feet of roof.