What Are Reasonable Span of Various Materials

The allowable span which a carrier can have so that it will not collapse depends on three things (for an overwiev see figure 1):

+ its cross-section geometry (see examples below in the geometry part)

+ its material (steel, wood or reinforced concrete)

+ on how you will apply the load on it (is the weight in the middle of the carrier or at one side)

Remember: NEVER use concrete or similar materials like stone without reinforcements of steel or similar for a carrier! The possibility that it will colappse is almost certain!

You can see an overview of a common problem involving a carrier as it would be used for a roofing or for hanging other loads for instance meat.

Figure 1: An overview of a the most common use of a carrier

--HTP Petros 15:57, 13 January 2010 (UTC)