Restoring a +300-year-old, Italian, Stone Masonry Home
The goal was to modernize the thermal efficiency and seismic safety of the house while maintaining the historic and traditional integrity of this beautiful ‘borgo’ (hamlet) home. The construction process took about a year and was completed in February of 2011. At the time, there were two personal income tax breaks available to homeowners for this type of project, both of which were taken advantage of by our client in this case. The first was a general house renovation tax break for 36% of expenses, and the second was for 55% on renovations that enhance the energy performance of the building. As with many historic structures in Italy, there were a number of existing challenges:
Thermal envelope: Because the home is located in a traditional ‘borgo’, two sides of the house share the wall with the neighbors, removing the option of external insulation. In these cases, we used thermal insulating plaster on the interior to resolve thermal bridges that might otherwise cause future problems with mold and condensation.
For the stone masonry that faced out, we were able to use an external insulation system (“cappotto” in Italian). In this way, we maintained the beautiful stone work as visible from the interior. Leaving the stone exposed to both the interior and the exterior would not have allowed the building to meet minimum energy performance requirements.
Replacing the roof: The original ceramic tiles of the roof were set aside during the construction process for reuse in the final stages. The structure of the roof, however, was altered considerably. The existing wooden structure needed laminated wood beam reinforcements to meet seismic norm requirements. We added an airtight layer to the roof profile, with a vapor retardant membrane on the inside, that connects with the airtight layers of the perimeter walls (note: in the photo, they had not yet been connected). We added wood fiber insulation, in order to provide for thermal comfort in both winter and summer.