Green Office BuildTog++ in brief
This is a building for public offices in Ferrara, Emilia Romagna, a place with cold winter and hot summer.
The building is located near the historical city centre, but this is not an historical building. It’s a former school, renovated in the ‘80s.
The heated surface is about 1334 m2. Two sides of the building face a private courtyard, the other two sides face the public street; these streets are quite narrow and this is a problem for external insulation. There are bricks on the facade, typically for this area, and regular windows on all the facades. There is a big skylight on the roof, that causes overheating problem during summer period.
At the moment the energy efficiency of the building is really bad. The heating is produced by a district system and there are pv panels on the flat roof, but they are not working.
The challenge and the targets
In Italy renovated public building must be NZEB and there are public funding to support these kind of works.
The intervention aims to promote deep renovation also in the private market, so the idea is to make visible the energy efficiency.
The renovation involved the whole building, the NZEB level will be reached using a balance of intervention on envelope, system and renewable energies.
The project involved the construction of a green roof, that it’s not quite common in Italy, but it’s interesting in this kind of weather. This green roof is a low maintenance one, with light thickness, about 8 cm, with plants that don’t need specific treatment, like draught resistant plant.
There are ventilated facade with 20 cm insulation panel on the facade overlooking courtyard and less insulation without ventilation on facades overlooking the streets. Sun-shading are provided to reduce overheating; internal sunshading is not the best solution for overheating problem, but is better for use natural lighting.
The NZEB standard oblige to go away from the district heating to respect the renewable energy and summer cooling criteria. The idea is to use an heating pump for heating and cooling and install new pv panels over the green roof, that also sunshade the roof.
The intervention costs about 1 mln €, with an energy saving around 82%, savings 16’000€ per year, not so much compared with the construction costs, but the public owner probably doesn’t pay anything thanks to public competition.
Talking about the financial part of the project: the costs will be covered 65% by Ministry of Economy funds, 23% by EU funds managed by Emilia Romagna Region and 12% by Province of Ferrara itself.