This study aimed at the inspection and repair of the Municipal Council and Jail timber roof to guide the heritage of building restoration. This is a historical building of Colonial Brazil period, located at XV of November square, in Florianopolis city. The project was held on three different steps: (i) identification of wood species that composes the original roof structure, (ii) inspection of the roof structure in loco and (iii) structural roof re-design, with another commercial wood (Mezilaurus itauba Meisn.). The species identification was carried by the analysis of the organoleptic and anatomical properties of 5 samples. Microscope slides were manufactured for anatomical analysis with light microscope. Moreover, in loco inspection, percussion, scarification and non-destructive techniques were used. The moisture content of the inspected structural timber elements was evaluated with a resistive hygrometer. Eleven principal structural elements, organized in 36 sections, were inspected. The identification of the structural elements was made according to a previous survey of pathological manifestation. The sections were classified as: Not Damaged, Partially Damaged and Damaged. Within the 11 elements analyzed, 5 presented at least one damaged section, another 5 partially damaged and only 1 presented integrity in all sections. In detriment of the identified damages, the restrength of all wall plates and hip rafters was determined, as well as the timber recognized as being freijo specie (Cordia goeldiana), not suitable for the structural usage, and the elements that are able to present any type of damage or degradation, compromising the structure at the restoration moment.