intervention strategies for renovation of social housing estates

Approaches to renovation interventions in the Netherlands, proposals for Rome chapter 4
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the North in particular (province of Bolzano) 6 . In the end, presences of further improvements
per proposal have been identified.
To compare different energy consumptions of buildings Casa Clima uses the so-called
“classes” system. The standard of EPDB, in fact, proposes two types of scales: continuous
scale and classes. The continuous scale is simply a graduated scale defined by best practice
(e.g. zero energy building) at one end and the worst case at the other end. A specific
building finds its place on this scale according to its energy performance indicator. In the
class system, buildings are sorted into seven classes A to G. The best buildings are in class
A, buildings with energy performances in line with standards in classes A or B, buildings
better than the building stock average in classes C or D, and other buildings in classes E to
G, depending on their performance with respect to the building stock average for the same
type of buildings (Roulet & Anderson, 2006).
Current conditions of the block are characterized by prefabricated concrete panels provided
with window frames and glazing attached to the concrete framework. Their thermal capacity
is very low (0,69 W/Km2K). The current energy building consumptions (101kWh/m2) place
the block into Class E. This Class is far from the minimum one required by the certification
taken as a reference (at least Class C, 70kWh/m2).
To satisfy the minimum energy consumption required by the regulation, the called ‘softproposal’
has been formulated. It is easily feasible: it does not imply the temporally removal
of residents, does not require particular technically expertise and is financially affordable,
and brings a quick yield on the investment for the resident.
It consists in adding an interior thermal insulation layer to all interior walls of the dwellings,
including the roof and ceiling of
the porticos. Together with the
substitution of single glazing
with higher performance double
glazing it leads to a shift of 101
to 90 kWh/m2a, corresponding
to Class E and D. The total cost
was roughly estimated around
900.000 €, per dwelling € 9.000
(2005).
However, better energy
consumption could also be
reached by means of further
envelope directed physical
measures. Therefore, a more
articulated proposal was
formulated, the called ‘high-level
proposal’. It regards not only
improvement of thermal
performances of roof and ceiling of porticos, but also substitution of entire building envelope
with a high performance facade. This is formed by light insulated prefabricated panels
characterized by a double layer of cellulose fiber, 19cm thick and a U value of 0.19 W/Km2K,
and external side in fibrocement panels. With a total cost of around 1.100.000€, this
proposal leads the consumption shifting to Class A (28 kWh/m2a).
Clearly, the appearance of the building could be strongly altered by means of the new
panels.
Nonetheless, the ‘high-level proposal’ does not employ alteration of the functional layout.
Thus, a third proposal that was called ‘REproject’ was defined to investigate to what extent
further physical measures could produce additional improvements comparing to the highlevel
proposal.
Solutions to expand the building size have been formulated. Empty rooms on the first and
second floor were filled with new dwellings and porticos with additional commercial activities.
Existing flats extended by attaching livable boxes to the façade. This latest measure could
diminished. The EPA-method is now being “translated” to the EPBD classification.
6 The subject has been further explored in the Paper by Riccardo, F., (2007) Beyond new clothes for renovation of
social housing. Problems, strategies and future perspectives for the city of Rome, (also CD-Rom) in congress
proceedings “XXXV IAHS World Congress on Housing Science. Planning, design, construction, performance”, Melbourne,
Australia 4-7 September 2007
26. D
CURRENT
CONDITIONS
SOFT-PROPOSAL
REproject -
PROPOSAL