The changing moisture content of some of the roof timbers at Lincoln Cathedral were surveyed as part of a national study to inform better preservation of medieval roof structures. Resistance moisture meters were installed in the roofs of the Consistory Court and Ringers' Chapel, in an attempt to assess their vulnerability to Deathwatch Beetles and Oak Rot Fungus. The survey recorded a seasonal variation of moisture content at the surface of the timbers, with more stable moisture levels deeper in. {1}