A full historical recording of Dronfield Hall Barn by Archaeological Research Services Ltd of Bakewell is currently taking place. Conforming to English Heritage standards, the survey will record the existing condition of the grade II* building before any development work begins.
The completed report will build upon research and recordings by Stanley Jones, who provided the first detailed written account of the Medieval timber frame and internal structure of the barn.
A full photographic record will be produced, with images captured in both digital colour and as black and white negatives. High contrast monochrome photos often produce the best results when recording architecture, capturing a long lasting and durable archive for the future. General photographs of the barn will be combined with detailed images of interesting features and a hand drawn record of cross sections and floor plans.
The final report will include a discussion of the possible historical construction and usage sequence of the building. Historic building recording may identify opportunities for hidden structural or architectural features to be exposed during conversion of the barn into a heritage centre.
Following the recording, a geophysical survey will be undertaken at Hall Barn to determine the most appropriate sites for further archaeological investigation. Exposing features below ground level may help to further our understanding of the historic usage and chronology of the site. Test pits scattered inside and around Hall Barn in 2009 uncovered a Medieval beaten earth floor, believed to be the original floor surface of the building. Beaten earth floors consisted of compacted bare soil, often covered in rushes or straw for insulation and to gather debris. The floor would be swept out and replaced regularly.
The two most commonly used geophysical techniques are magnetometry and resistivity. A magnetometer has two sensors. One measures the Earth’s magnetic field, and the second detects any distortions in that magnetic field caused by features in the ground. Plans of these variations can be plotted on a computer, producing a ghostly shadow map of walls, ditches and floor surfaces hidden below the surface.
Resistivity uses a weak electronic signal, passed between two prongs inserted through the soil. If the current hits a concealed wall or object which does not conduct electricity well, a computer will measure the resistance. When passing through a ditch, pit or an area of waterlogged ground the current will flow quickly with no resistance and that too can be measured. Most British archaeology appears within the top half metre of soil so excavations do not need to be deep!