Løvåshagen- Passive Housing
Fyllingsdalen, Bergen, Norway
PROJECT TEAM & PARTNERS
- Private developer and constructor in cooperation with research
centres:
ByBo AS, Arkitektkontoret
ABO AS, SINTEF Byggforsk og Husbanken - Project leader: Engineer Jan Kavlie-Jørgensen
- Building coordinator: Jansen Prosjektstyring.
CONTRACT VALUE
Approx € 31,25 million
FUNDING
Private development/building company; ByBo AS
TIMESCALE
2006-2009
DESCRIPTION OF THE PROJECT
Løvåshagen is a pilot project
which consists of 28 passive and 52 low energy houses. It has been
built as a model project for increased energy efficiency of houses,
universal design and architecture for the future. The project has
been approved as a pilot study by the "Housing bank"
(public body) and nominated to be one of the so called
"Lighthouse projects" of Enova (Enova SF is a public
enterprise owned by the Royal Norwegian Ministry of Petroleum and
Energy).
Facts:
The Løvåshagen project consists of 80 apartments -28
passive houses and 52 low energy houses- where energy saving is
taken seriously. The 80 houses have extra insulation,
"superinsulated" windows and a ventilation system which
is recycling the heat and sun capturers on the roof.
Løvåshagen is built in an area that is safe from traffic
and with nature as the nearest neighbour.
Possible energy saving per year is estimated to be around 550 000 kWh compared to normal housing. Estimated energy delivery would be between 74 and 101kWh/m²/year. Average size is 80 m² (ranges from 75 up to 89 m²). Average temperature per year in Bergen is: 7.8°C (winter in Bergen is -10°C). Yearly estimate horizontal radiation: 87 W/m²
Factors that contributed towards low energy consumption:
Cold bridges and transfers/channels have been reduced to a minimum.
Windows and doors have very low U-values and the building mass has
extra insulation. Double wind protection with tape in all
"borders"/"seems" to minimise air leaks. The
buildings have good air and light conditions. All apartments have
balanced ventilation with a highly effective rotating
heat-recycler. An additional measure is the "in and out"
switches that put the houses into "standby mode/pause"
when people are out. Finally, the houses are equipped with solar
collectors for heating.
Heating: The Passive houses have two solar collectors, both on the roof which primarily secure hot water but also covering some floor heating and a radiator in the living room. The low energy houses have an electric boiler for hot water, floor heating and for a heater in the living room of 1000W.
Cost:
The cost has not been analysed yet as the necessary figures for
this are not available. Estimated extra cost compared to normal
houses are 120 -140 Euro per m².
PROJECT TARGETS AND LEGISLATION
All passive houses have been tested on pressure and the result is
better than -or the same as- the standard of 0.6 air changes per
hour. In the low energy houses random testing has measured that all
apartments were according to the required standard or better than
the standard.
Total net energy need for the passive houses is estimated to be 91kWh/m²/yr, and delivered energy (electricity) is estimated to be 74kWh/m²år. Sun heating covers 17kWh/m²/yr.
Average energy need for the low energy houses is estimated to be 101kWh/m²year, whereas delivered energy (as electricity) is estimated to be the same: 101kWh/m²/yr. Thus all delivered energy is electric.
Since there is no Norwegian standard for passive houses, Løvåshagen has been built after the standards from Austria. The ambition of ByBo AS and Enova is that Løvåshagen will become the first project to be certified and receive a Norwegian energy label according to Norwegian rules.
INNOVATIVE PRACTICE
A network of people with long experience has helped reduce the
extent of bad solutions in advance of the building process. The
innovative part lies just as much in making old and bad solutions
better and in making new solutions simple, for those who are
supposed to use them in construction or as consumers/users
afterwards. As a result:
• Wall constructions are especially conceived to cover the
need for insulation and security in the building process.
• A technical cell has been put in place only to take care of
all technical installations linked to heating and ventilation
• Balconies are constructed in a special way to minimise the
cold bridges and avoid humidity problems.
CHALLENGES FACED
The main challenges faced can be summarised in the
two areas below:
Planning:
Letting new standards and demands for universak design
to be fully developed and at the same time allow the architecture
to reach its full potential. Cold bridges had to be minimised and
energy storage must be given priority. The passive measures taken
in the building should be ensured but not be an inconvenience.
Execution:
A multitude of details have been examined and revised in order to
have full control of how it is being executed. All the
professionals who were involved in the building process received
training in detail, which was crucial in order to achieve the
specific measures that are necessary for a passive house or a low
energy building. Detailed routines that could help control the
construction process have been put in place on the building
sites.
LESSONS LEARNT
- To increase the effect of energy efficient construction one should plan for bigger areas which could share common infrastructure for renewable energy and reduce the waste transport and energy waste in the construction period.
- Focusing on details can be decisive in order to achieve severe demands on "tightness".
- Training of those executing the work is decisive for a product to become as planned. It is important to make those in charge of executing the work/buildings understand what the consequences could be if things are not done correctly.
- Customers are not yet aware of the differences between normal housing and passive houses/low energy houses. It is therefore necessary for public authorities to focus on passing information about which kind of housing is energy efficient. Labelling of houses/housing and companies is also of help.
CONTACT DETAILS
ByBo: Kjetil Helland; kh@bybo.noTlf: 55 90 23 80 - Fax: 55 90
28 20 - P.B 1137 Sentrum, 5609 Bergen