Abstract
The history of a building is the history of its constructive elements. Therefore, substituting a historical element should be the last choice, after trying to repair or reinforce it for new uses. This paper tells the life history of a 7 m long wooden beam and the jack vaulting floor it supports, placed on the 2nd level of an old tower, from its original construction, history, modifications and pathologies till its recent restoration designed by the authors. The beam, seriously affected by a termite attack that had almost eaten away 1.5 m at one side, has been repaired with a prosthesis that was made in situ, unloading it by means of propping up the whole tower. Some of the historical joists whose length had also been shortened by wood rot have been repaired with prostheses to help them rest on the walls. At the same time, the beam has been reinforced to accept public loads with an alternative and non conventional system. This system has managed to reinforce the existing beam withing the 3 cm of the historical pavement mortar. This invisible device has made it possible to respect both the matter and the appearance of the beam as well as the historical configuration of the upper and lower rooms of the building, not to mention the interesting unevennness and depressions that form the orography of the old upper pavement, due to historical floor deflections and subsidence of the building.
