Sto provides products & systems for building facades, external wall insulation, interior walls and ceilings, acoustics, industrial floor coatings, and concrete restoration. StoTherm by Sto was used in the retrofit and vertical extension of a housing estate in Bolzano, Italy.
The architects opted for a new building envelope and vertical extension, combining energy efficiency with a distinctive design to revitalize the generic structures. These 1950s residential buildings were refurbished for energy efficiency, reducing energy use by 40-60% and upgrading from CasaClima class G to A. Vertical extensions added 14 units, enhancing both housing capacity and urban appeal.
Facade structure
The insulated facade creates a cohesive "skin" over the original building and its new top floor, unifying projections and recesses into a dynamic, harmonious design. An external wall insulation system was added to improve the original buildings' thermal performance, while cross-laminated timber panels provided a lightweight, load-bearing structure for the vertical extension. The buildings were clad with 20cm and 15cm insulation, creating subtle facade recesses and improving the U-value. The vertical extension mirrors this design with insulated timber panels, maintaining consistency while keeping the CO2 footprint at 19.1 kg CO2/m².
Products
Contrasting light and dark grey renders in different textures create a striking facade appearance:
- StoSignature, Fine 30 (Plaster Stolit K 1.5 + Stolit Milano, color 16288): fine-textured plaster, smoothed and sanded over the surface
- StoSignature Individual + effect coating (StoMiral K 3.0 render, untoned + Glaze StoCryl V 400, color 16291): finishing render, brushed on all sides + glaze, brushed over the entire surface
| Location | Bolzano, Italy |
| Type of building | Housing estate |
| Architect | Area Architetti Associati |
| Products used | StoTherm |
