Report on an X-Ray Fluorescence (XRF) analysis undertaken to determine the original function of re-used floor joists at Lincoln Lane Farmhouse, Sixhills. This was done as part of a research project conducted by the Society for Lincolnshire History and Archaeology's Building Recording Group (RUBL). It was proposed that the 12th century timbers, originally from the nearby Sixhills Priory site, may have been cut as sarking boards, which would have a higher levels of lead on the face in contact with the lead roof sheets. It is also supposed that they would have higher calcium readings, as calcium carbonate (chalk) was regularly used to protect timbers in contact with lead roof sheets. The analysis found no clear evidence to support these hypotheses. {1}