05 April, 2022

Theoretical Structural Archaeology - Thirty New Discoveries


  1. Introduction 

1.1 What I study 

  • I reverse engineer archaeological buildings & structures from posthole evidence.

  • Using  traditional architectural technical drawing, CAD, and deductive reasoning to build functionally accurate models.

  • Working with the complete scaled dataset to identify basic structural components.

  • I started in 1990 [1] & published online here since 2008. {so they are not all new}

  • Postholes are the most numerous archaeological features on certain types of sites.

  • Thus, Theoretical Structural Archaeology represents a set of analytical techniques for understanding certain archaeological data sets.

1.2 What qualifies as a discovery 

  • Insights & discoveries of potential national or international importance.

  • Completely original & not copied from other scholars or site reports. 

  • Outside of my primary work as a professional archaeologist. 

  • Work done in my own time.

1.3 Wider context of Theoretical Structural Archaeology

  • My basic methodology has been peer reviewed in the USA. [2]

  • Theoretical Structural Archaeology is maths & science based where possible. 

  • Models are refined by looking for errors, inconsistency and poor mathematical fit.

  • To the best of my knowledge I am the only UK archaeologist working on the interpretation of timber built environments. 

  • This was the basis of a PhD at Newcastle, but evidence based archaeology and science proved incompatible with image based post-processualism subjectivism.

1.4 Format - 30 page A4

Brief and concise summary of the insight, idea or discovery.

  • Details, definitions & Implications - maximum of six.

  • Summary or example illustration as space permits. {this is a very visual subject}.

  • To Fit on A4 sheet, ie. 30 Pages {+ this one}, in 3 groups;

  • Basic structural modelling {from c. 430 lecture / video slides} 1-7

  • Advanced Structural Models & Case Studies 8 - 22

  • Archaeology of Hadrian’s Wall { from 3 Videos + 120 lecture slides} 23 -30

2. Basic structural modelling 

2.1 Reverse Assembly Truss

The most important concept and the basis of any understanding of post built buildings is the difference between normal and reverse assembly. {sectional view}

  • A Truss is composed of a rafter pair with a horizontal Tie across the bottom.

  • This triangle is the basis of the roof as understood; a building is a roofed structure.

  • Assembly is the detailed order in which the structural components are put together; i.e. foundations first to thatch last. 

  • Normal Assembly; in a building with load bearing walls, the load of the roof is supported on a solid wall or timber frame, the roof truss and its tie sit on top.

  • Reversed Assembly; in a building where the mass of the roof is supported on posts, it is practical to place the posts directly under the ties.

  • This arrangement allows for;

  • Offset posts which simplified jointing

  • Lightweight wall construction

  • Still present in Far Eastern tradition, {performance in earthquakes}.

2.2 The Offset Tie

Apparent irregularity in the layout of posthole foundations can be explained as a product of offset jointing, which simplifies construction and allows the rafter pair to be at right angles to the roof plate & ridge.

  • This single observation explains the ground plan of reverse assembly structures.

  • It is present in LBK Longhouses, roundhouses, & larger circular buildings {Classs Ei}.[3]

  • Enables the distinction of structures such as floors from roof supports. 

  • It probably originates in PPNA as it is present at Göbekli Tepe.

2.3 Relationship between postholes & trees

A long tradition of forestry and woodland management has developed a detailed understanding of trees which can be directly related to the remains of archaeological timber structures. Through data contained in species specific yield tables.

  • DBH is diameter at breast height {4’},  is good approximation for size of the post pipe

  • The key metric is the height of crown formation {c.top height }

  • Larger trunks can be box sectioned

  • Coppice is method of growing multiple stem on single root system

  • Yield tables can form the basis of modelling

  • The general parameters of buildings and structures are in part a product of the local availability of timber .


2.4 Relationship between trees & buildings

tbc . . . . .

1. 'Excavations at the Orsett ‘Cock’ enclosure, Essex, 1976'. G. A. Carter (1998): East Anglian Archaeology Report No 86. [Illustrated by L.E. Collett]
2. Building the Past: Studies of Prehistoric Wooden Post Architecture in the Ohio Valley-Great Lakes Region, edited by Brian G. Redmond and Robert A.
3. Neolithic houses in northwest Europe and beyond, 1996, Neolithic Houses in North-West Europe and beyond (Oxbow monograph 57), T.C. Darvill , Julian Thomas (Eds).