The article outlines the different construction techniques used from the 13th to 16th centuries in Italy, particularly in Tuscany, to support and control paintings on wood. When the support is definitely deteriorated, it is often necessary to intervene by applying new structures, which must be worked out in relation to the movements of the wood. Two new solutions are proposed here: one based on sliding runners and helical springs inserted in the crosspieces, and the other on a frame with independent, sliding crosspieces by springs.