The reasons the housing society decided to go for thermal insulation were
to improve the comfort of inhabitants and achieve energy savings, since there
was an inefficient use of heat energy and energy for heating water. The inefficiency
was particularly caused by inconvenient insulation characteristics of the
external material and by the behavior of the inhabitants.
The housing society formed by the inhabitants of the building became independent
in 1995. At that time the society didn´t have enough financial resources
to realise such a project. Later, because of high energy bills, the board
of the housing society, after an agreement with the members, decided to
the possibilities of the project and in 1998 began to take necessary steps
such as looking for suitable companies who would be able to realise the
Results of the Energy Audit
In 2000, an energy audit was performed by Ekowatt, a renewable and energy
conservation center, in order to ask for a financial support from the government.
The audit determined energy savings potential. It presented and evaluated
three possible options of energy efficiency measures that could have been
taken into account. Finally, Ekowatt recommended that the society adopt the
option of thermal insulation of the external walls would be done. As a low
cost measure, Ekowatt proposed reparation of the windows on the north side
and reconstruction of the heating system. The energy audit also recommended
informing all of the inhabitants about the right way of aeration. The overall
energy savings of the suggested option were calculated at 1.195 GJ per year,
which represents a 34,6 % energy savings compared to the previous state. This
number includes the consumption of energy for heating water as well.
Economy of the Project
The overall cost of the thermal insulation suggested by Ekowatt came to 129.000,-
EUR. The audit counted on government support of 15%, which meant around 18.750,-
EUR. Finally the housing society got just 12.500,- EUR (or 10%) from the government.
Work on the thermal insulation and replacement of balconies was finished at
the end of 2001. The actual cost increased to around 184.000,- EUR, including
the balconies. The higher cost of the project was caused by the higher prices
of the chosen company. Of course the project could have been realised for
a lower cost but the inhabitants prefered to hire a rather costly but well
known company. Till now the housing society has been able to cover 106.250,-
EUR from its internal sources by increasing its repairs fund. The rest of
the money was borrowed from the company. The society pays the firm 3.125,-
EUR on a monthly basis, and the total claim should be paid up by 2004. In
the near future the society would like to reconstruct the heating system,
since there is no regulating mechanism at present and legislation has been
enacted. It will require an additional 15.625,- EUR. If the housing society
is able to get enough money together (6.250,-EUR) the windows on the north
side will be also renovated.
Energy efficiency projects on prefabricated buildings do not come very favourably,
because the return of investment is usually very long. The return of the investment
of our project was estimated at 15 years. Most of these projects function
as a chain reaction. Once there is a prefabricated block of flats in the neigbourhood
getting renovated, the inhabitants of the building next door are willing to
start the project on their own building.