Dating historic buildings

Lead head with date (Calloway, The Elements of Style)Broadly speaking there are three methods of dating.

  1. Style: Buildings are often roughly datable by their style. See the style section of this website for an introduction and bibliography, with pages and bibliographies on specific styles. Dating by style depends on having a corpus of firmly dated examples. How are these firmly dated?
  2. Records: Mostly exact dating derives from original documents or plans which give a building date. These could include architect's plans, building accounts or contemporary descriptions of the building in the course of erection, or newly built. This site gives guidance on researching documentary evidence. Beginners might like to start with the basics of researching an historic building.
  3. Physical evidence from the building itself could include an exact date, either from an inscription or dendrochronology. A date may appear on a datestone over the door, or on particular items, such as lead drainpipes, or materials such as bricks, which may have the maker's name stamped within the frog.
    • Dendrochronology can give the exact year in which timber is felled and is especially useful for vernacular buildings that are hard to date by style. There are several laboratories in Britain and Ireland, which make their results available inthe journal Vernacular Architecture, published by the Vernacular Architecture Group. The latterhas created an online Dendrochronology Database from the lists published annually in the journal.
    • A new method of dating brick and tile by rehydroxylation kinetics is still at the research stage.
    • Analysis of the fabric could also also show phases of building and alteration, which could then be roughly dated either by style or materials. For example frogged bricks appear from the early 1800s. Bricks can also be roughly dated by their size prior to modern standardisation.
Collections of physical samples: