How old is Great Coxwell Barn?

Core samples from wooden timbers at Great Coxwell Barn Oxfordshire

For many years it was thought that Great Coxwell Barn was built in the early 1300s, but recent scientific testing has shed new light on this theory.

What we did

In 2014 a scientific method called dendrochronology (a dating method that uses the growth rings of long-lived trees as a calendar), was used to narrow down when the barn was actually built.

Taking the samples to age Great Coxwell Barn
Taking samples from the timbers at Great Coxwell Barn
Taking the samples to age Great Coxwell Barn

Using a cherry picker for access, 16mm diameter core samples were drilled from ten of the timbers supporting the vast roof. They were then taken away for analysis and dating. 

The analysis showed that the wood used for the roof timbers was felled from 1253 onwards. One of the samples still had the bark edge preserved making it possible to say this had been felled in the winter of 1291/92. Samples from two other timbers in the barn also came from the same parent tree.

We know it was common practice at the time to build timber frame structures with green or unseasoned timber, usually within 12 months of felling.

The results

So to the question “How old is the barn?” we can now answer that it’s most likely that the barn was under construction in 1292 or shortly after, making it about 723 years old.