Editing Lumber (section)

===Historical Chinese construction===
Under the prescription of the ''[[Yingzao Fashi|Method of Construction]]'' (營造法式) issued by the [[Song dynasty]] government in the early twelfth century, timbers were standardized to eight cross-sectional dimensions.<ref>{{cite book|last1=李|first1=誡|title=營造法式|date=1103|publisher=Song Government|location=China|url=https://zh.wikisource.org/wiki/%E7%87%9F%E9%80%A0%E6%B3%95%E5%BC%8F/%E7%AC%AC%E5%9B%9B%E5%8D%B7|access-date=8 May 2016}}</ref> Regardless of the actual dimensions of the timber, the ratio between width and height was maintained at 1:1.5. Units are in Song dynasty inches (31.2&nbsp;mm).
{| class="wikitable"
|-
! Class !! height !! width !! uses
|-
| 1st || 9 || 6 || great halls 11 or 9 bays wide
|-
| 2nd || 8.25  || 5.5 || great halls 7 or 5 bays wide
|-
| 3rd || 7.5 || 5 || great halls 5 or 3 bays wide or halls 7 or 5 bays wide
|-
| 4th || 7.2 || 4.8 || great halls 3 bays wide or halls 5 bays wide
|-
| 5th || 6.6 || 4.4|| great halls 3 small bays wide or halls 3 large bays wide
|-
| 6th || 6 || 4 || pagodas and small halls
|-
| 7th || 5.25 || 3.2 || pagodas and small great halls
|-
| 8th || 4.5 || 3 || small pagodas and ceilings
|}

Timber smaller than the 8th class were called "unclassed" (等外). The width of a timber is referred to as one "timber" (材), and the dimensions of other structural components were quoted in multiples of "timber"; thus, as the width of the actual timber varied, the dimensions of other components were easily calculated, without resorting to specific figures for each scale. The dimensions of timbers in similar applications show a gradual diminution from the Sui dynasty (580–618) to the modern era; a 1st class timber during the Sui was reconstructed as 15×10 (Sui dynasty inches, or 29.4&nbsp;mm).<ref>{{cite journal|last1=王|first1=貴祥|title=关于隋唐洛阳宫乾阳殿与乾元殿的平面_结构与形式之探讨|journal=中國建築史論匯刊|volume=3|page=116}}</ref>