|New experimental homes will heat themselves|
|Friday, 12 September 2008 10:20|
|“We’ve learnt the lessons of the 1970s,” construction officials insist. DENSITY, compactness and insulation are the current focus of architects and planners. New housing in Finland is being built more compactly than previously so that heating is more energy- and cost-efficient. Constructed in the right way, advocates maintain, compacter housing does not even require a heating system.This sort of design is being experimented north of Helsinki in Tikkurila, Vantaa, where semi-detached houses are being built without a separate heating system.
The house will draw its heat primarily from the people, household appliances and lamps it contains. Jorma Vuoritsalo realises that, for many people, it’s hard to believe that a house’s contents alone could provide adequate heat, but he remains convinced that he won’t need to freeze in his new home.
Quite the opposite, according to Pekka Haikonen, director of development at Paroc, a company specialising in building insulation. He argues that, when built correctly, self-heating homes are perfectly pleasant since the internal temperature is self-regulating and heat is naturally distributed evenly. Paroc, along with the Technical Research Centre of Finland (VTT), is responsible for the design and execution of the Tikkurila development.
According to Paroc’s estimates, residents of the planned homes will face heating expenses of some 350 euros per year, whereas the annual bill incurred in heating the current average single-family house is closer to 1,200 euros. Even more strikingly, the energy consumed annually by one of the new experimental houses will be less than a sixth of that currently swallowed by a more conventional model.
An unpleasant flashback?
Compacter housing models are not an easy idea to market to Finns since they often provoke fears of poor air circulation and mould. Many have unpleasant memories of the houses built in response to the energy crisis of the 1970s, which were soon riddled with damp and mould-related damage.
But the lessons of the 1970s have been learnt, Helena Säteri reassures people. The director general of Finland’s environmental administration explains that the key is to ensure that air circulation in densely-built housing is both thorough and effective.
Pekka Rönkkö is also quick to calm fears of stuffy interiors. A product manager at Paroc, Rönkkö’s role as a technical expert on the Vantaa project has left him confident that every room in the new houses will contain fresh, well-circulated air.
Circulation won’t come in the form of an unpleasant draught, however, since air coming into the building will first be heated. Normally, this process will not require any power, since it will utilise the heat already inside the house.
When required, though, air entering the house can also be heated electrically. This may be necessary during winter following a period when the house has been empty and the internal temperature has fallen, when the family has returned from a winter holiday, for example.
Improving older buildings
Older houses are not easily modified in order to make them dense enough to go without a separate heating system, but they can certainly be made more energy-efficient, Rönkkö says. The key is to insulate them properly.
In particular, he encourages people to concentrate on insulating the building’s foundations, calling it a small but lucrative investment which fundamentally improves a house’s energy-efficiency and dramatically reduces annual electricity expenses.
Double glazing for the windows is slower to pay for itself long-term, he concedes, but remains a worth-while investment. Moreover, better-insulated windows reduce unwanted draught, which makes a house a much more pleasant place to live in.
Rönkkö also has a message for the housing cooperatives of apartment buildings: when renovating the building’s facade, it makes sense to improve insulation at the same time.