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.
Girder roof structure.
This article series describes and illustrates the different types of support that prevents roof sagging and wall bulging at buildings including definitions of collar ties rafter ties and structural ridge beams.
The figures are based on quality materials.
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.
A girder is commonly used to build bridges.
A girder ˈ ɡ ɜːr d ər is a support beam used in construction.
For heavy roofs or in areas with substantial snowfall or winds call your local building department for code requirements.
Beams support the structural integrity of buildings mostly residential structures and can be found in floors walls ceilings roofs and decks.
It is the main horizontal support of a structure which supports smaller beams.
A girder truss is designed to support other secondary roof supports.
In areas with mild climates patio roofs are generally designed for loads of 30 psf pounds per square foot.
Beams are the choice of structural member because of their incredible load bearing capacity against all conditions.
The tables below give maximum spans for rafters and beams.