Exploring the environment in Iron Age houses, a preliminary investigation.

Within the history of Experimental Archaeology there has always been a great interest in the questions surrounding how a particular structure was built; how much material it would use? How long would it last? And what footprint would it leave behind? There has however been very little investigation into what the environment was like within the structures that we reconstruct; What were they like to live in for a prolonged period of time? What effect would this environment have on your body?

The Little Woodbury house at Butser Ancient Farm.

I decided that this was a question that needed investigation to better understand the people living in the past, and the impact of their environment on their health. It is a very big question and has many different elements to it so I decided that I would choose one area to focus on and then build up the research to a much bigger project looking at all the different elements. The first element I decided to focus my research on was that of the air quality within a thatched house with an open fire.

Over my time working in thatched houses with an open fire I observed peoples reaction to the smoke. The minority seem not to notice the smoke above their heads but more often than not a visitor will cough and make a comment about the smoke inside the house. Visitors are only ever in a house for a short period of time, I have stayed in such a house for a maximum of a week at a time but what would it be like to live in an environment like this for a lifetime?

The smoking fire inside the Little Woodbury at Butser Ancient Farm.

In Feburary 2013 I was fortunate to be invited to take part in an Iron Age living experiment at the Eindhoven Museum. This would involve a group of around 20 people living in reconstructed European Iron Age houses for a week as Iron Age people. This was the perfect opportunity to test the air quality within a thatched house with an open fire in a ‘real life situation’ (the houses being used would give a better impression of the environment within the house when in use than running the experiment in a dormant structure).

Some of the participants in the 'living experiment'.

In order to measure the air quality within a house I used a very basic method (there are much more scientific methods to measure air quality however my budget was limited. I hope that this experiment will lead to future work where these sorts of instruments can be used). Sample cards would be hung within a house being lived in for 12 hours at a time before being changed for a period of 6 days.

A sample card is a small square of card with a sticky blob in the centre that will catch particles in the air (including microscopic ones). These can then be counted and the results used to better understand the air quality in the environment being tested. There were two houses being lived in during the experiment so both environments were tested. Five sample cards were hung in each house in random locations. Five more were hung up in the outside environment away from the living experiment. These ‘outside’ cards would be used to compare the air quality within the houses to the air quality within a modern day city (Eindhoven).

An example of one of the test cards underneath the microscope showing the particulates trapped.

Once the living experiment was over the sample cards were carefully brought back to England for analysis. Each card was placed under a microscope and the particles stuck to the centre were counted and recorded onto a table. These results were then plotted onto a graph showing all the data for each individual card for each day. An average was then taken and the results plotted onto a graph.

Graph showing the average particulate counted for each individual card over the six days. A: house1, B:house2, C:outside environment.

Graph showing the average particulate count for each separate area. A: house1, B:house2, C:outside environment.

The graph of results shows us that there is very little difference between the average particulates between the two different houses (A and B) while there are slightly more particulates on the test cards placed in the outside environment (C). This indicates that the environment in a modern city is worse than that inside a thatched house with an open fire. The more particulates there are in the air the more detrimental the environment is to your health. These results would indicate that the effect on a person living in the houses health would be less than the impact of living in a modern day city.

Before drawing a firm conclusion from these results we must examine the limits to the experiment. The equipment used was very simple and all results have relied on human counting. This means that only particulates that could be seen under a basic microscope were counted. This means that some smaller particulates will not have been accounted for. The same counting method was used for all samples though so the comparison between them is fair.

I hope that this small experiment will act as a preliminary experiment that a more thorough research programme can develop from.

This experiment has demonstrated that the environment inside of a thatched building with an open fire is not as bad as the outdoor environment in a modern city, something for anyone in a round house next time they are at Butser Ancient Farm.

If you would like to find out more about this experiment and my results or have a question then please contact me and I will happily discuss this further.

I would like to thank: Butser Ancient Farm, Friends of Butser Ancient Farm, The Eindhoven Museum, the WEA, and all mu Dutch friends who participated in the living experiment.