Editing Post and lintel (section)

==Span limitations==
There are two main forces acting upon the post and lintel system: weight carrying [[compression (physical)|compression]] at the joint between lintel and post, and [[tension (mechanics)|tension]] induced by deformation of self-weight and the load above between the posts.<!-- {{Clarify|date=March 2008}} Statics / Engineering 101---> The two posts are under compression from the weight of the lintel (or beam) above. The lintel will deform by sagging in the middle because the underside is under tension and the upper is under compression.

The biggest disadvantage to lintel construction is the limited weight that can be held up, and the resulting small distances required between the posts. [[Ancient Roman architecture]]'s development of the [[arch]] allowed for much larger structures to be constructed. The [[arcuated system]] spreads larger loads more effectively, and replaced the post-and-lintel system in most larger buildings and structures, until the introduction of steel [[girder]] beams and [[steel-reinforced concrete]] in the industrial era. 

As with the [[Roman temple]] [[portico]] front and its descendants in later [[classical architecture]], trabeated features were often retained in parts of buildings as an aesthetic choice.  The [[classical order]]s of Greek origin were in particular retained in buildings designed to impress, even though they usually had little or no structural role.<ref>Summerson, 19–21</ref>

===Lintel reinforcement===
The flexural strength of a stone lintel can be dramatically increased with the use of [[Post-tensioned stone]].