Anomalies in the Sintra National Palace wood-framing

The National Palace of Sintra in Portugal is a multi-storeyed national monument that portrays architectural/historical styles from the 13th to 19th centuries. The contribution of its many ancient wood-framing elements to its image is paramount. Generally, the assessment of historical buildings is focused mainly on (a) structural features concerning the brick or stone walls and the wooden floors, or (b) highly valued decorative features such as frescoes, stuccos and façades detailing. Other elements such as window and door panels, verandas, foot panels and staircases are less frequently referred to even though their degradation mechanisms are many and complex. In this paper, the causes for deterioration of wood-framing are thoroughly described and their relative weight in the overall degradation is commented upon. A grading system for the degradation of wood-framing is proposed and the maintenance/rehabilitation/replacement measures better adapted to each level of degradation are described. A survey made of the wood-framing of the National Palace of Sintra is presented and thoroughly illustrated and some conclusions are drawn from its results. [PUBLICATION ABSTRACT]