Moisture damage risks of zero-energy buildings can be avoided
The EU is pressing home its demand for all new construction to be nearly
zero-energy by 2021. This energy target can only be achieved, and moisture
damage risks avoided, if design and construction quality is ensured. As for
the cost – energy efficient buildings in Finland carry a 2–7% higher price tag
over conventional construction.
The EU’s Energy Performance of Buildings Directive is revolutionising
construction Europe-wide. As a Member State, Finland, too, is committed to
reducing its building stock CO2 emissions.
builds will be outdated in less than ten years. Despite vast improvements in
the quality of construction work, mistakes are still rife. We need to raise
the quality bar, and soon, because ever-increasing renovation of our old
building stock is something we simply can’t afford,” explains energy efficient
construction expert Jyri Nieminen from VTT Technical Research Centre of
The energy objectives of low-, passive- or
zero-energy buildings can only be achieved if the necessary design and
construction quality are up to scratch. This will also go a long way towards
soundly eliminating the quality defects typically responsible for moisture
Responsibility for preventing moisture damage lies
both with the client and the construction and maintenance service providers.
The appointment of adequately skilled designers and contractors and effective
supervision of the interests of the client are the client's own
responsibility. Clear objectives based on performance must be set for the
building, and these must be verifiable at the commissioning stage.
damage in buildings has traditionally been caused by leaking piping systems
and substandard work quality. Rainwater penetration into structures is a
classic sign of poor quality facade construction, or a simple lack of proper
maintenance. Other common causes of moisture damage include inadequate or
flawed waterproofing, incorrect storage of construction materials, and
carelessness and negligence during construction or maintenance.
efficient construction costs in Finland are 2–7% higher than conventional
construction based on current regulations. For example, the costs of a
multi-storey passive building constructed for TA Asumisoikeus Oy in Oulu,
Finland, were 3.3% higher than those of an adjacent conventional apartment
building of similar layout and design. Renewable energy installations are a
key source of extra costs in zero-energy buildings.
the energy demand of buildings is one of the most effective means at our
disposal for mitigating climate change. The smaller the building’s energy
demand, the easier it is to meet with the building’s own building integrated
Finland has leading know-how in this
field, for example in the thermal insulation of buildings, and
energy-efficient building services installations and window technology. To
promote the export of this expertise, working examples of Finnish solutions
need to be constructed. The results of Finnish research into energy efficient
buildings have been successfully utilised by turning developed building and
energy technologies into competitive assets for Finnish companies.
has been researching and developing zero-energy construction technologies
since 1990. The focus of this development work has been on solutions that
provide high energy efficiency and good indoor climate without compromising on
design or usability. Some of the key problem areas in low-energy construction
have been identified and resolved, for instance, with the help of sensors
installed in pilot buildings.
What is a zero-energy
A zero-energy building or, more specifically,
‘net zero energy building’, produces at least as much useable renewable energy
as it uses from conventional energy sources. Similarly, a nearly zero-energy
building meets at a significant proportion of its energy needs with renewable
energy that is produced either by the building itself or by a renewable energy
facility located nearby – as is the case with renewables-based district
Zero energy and zero emissions buildings are
currently the focus of intense global interest. The Norwegian University of
Science and Technology NTNU, for example, is developing leading solutions for
zeroing the carbon dioxide emissions of buildings.
applications for zero-energy buildings have been developed around the world.
Finland's first, and the Nordic countries’ leading example of a near
zero-energy high rise apartment building was completed in Kuopio at the end of
2010. Another is to be built in Järvenpää this year. In addition, zero-energy
single-family houses are also being built and developed in Finland.
IEA5 house, built in Pietarsaari in 1993–1994, is, according to the EU’s
Energy Performance of Buildings Directive, a near zero-energy building. The
house has been performing smoothly and greenly for more than 17 years.