Sweco architects design an ecological residential block for Kuninkaantammi
A right-of-occupancy apartment block designed by architects at Sweco will be finished in the Kuninkaantammi residential area in north-western Helsinki by the end of this year. The design process placed special emphasis on the use of renewable energy and piloting innovative stormwater solutions.
Kuninkaantammi is a new energy- and eco-efficient residential area by the Vantaa River and Helsinki’s Central Park. Environmental factors have already been noted in the zoning of the area, and energy efficiency guides the design and building processes. The goal is to make Kuninkaantammi a comfortable and diverse residential area for about 5,500 residents by 2025.
Planning ordinances create the basis for carbon-neutral construction
Kuninkaantammi is a forerunner in many climate issues. The local detailed plan requires low-energy building and the use of renewable energy. Additionally, the area combines an urban environment with a village atmosphere. The outer circle of the spiral-shaped street network is designed for vehicles, whereas the inner circle is dedicated to pedestrians. The goal is to encourage people to mainly use public transport, to cycle and walk.
Kuninkaantammi has piloted several solutions pertaining to the Carbon-neutral Helsinki 2035 Action Plan, which will guide future zoning.
“The carbon-neutral goal will only be achieved if renewable energy can be produced locally in a significantly larger volume than today,” says Suvi Tyynilä, Detailed Planning Team Manager for Kuninkaantammi. The roof surfaces at Kuninkaantammi are being utilised for the collection of solar energy. “Future zoning can also require participation in centralised regional energy plants, which produce renewable energy.”
The goal of Kuninkaantammi’s zoning is to encourage ambitious projects, such as going below limit values. In addition to energy efficiency, issues such as eco- and material-efficiency are being addressed as well, and the zoning requires that the mineral aggregate produced by the excavation of parking garages is used in the plots.
“Only half of the yards are positioned on top of the decks of parking garages, allowing for the building of rain gardens and the planting of large trees in the ground-supported areas which in turn increases the eco-efficiency of the area,” Tyynilä says.
Stormwater solutions benefit both environment and people
Zoning can widely impact the carbon footprint of urban development and ease the adjustment to climate change. Green roofs are a growing trend.
“At Kuninkaantammi all low buildings are required to have a green roof, and in newly zoned areas the requirement also applies to taller residential buildings,” Tyynilä states. Additionally, Kuninkaantammi is the pilot area for urban flood prevention and storm water solutions. “Rain and meltwater are stalled in the plots using e.g. rain gardens and are only afterwards directed to the regional storm water system.”
The first residents of Kuninkaantammi have given positive feedback about the comfortable gardens, and the good practices have begun to spread to other parts of Helsinki. It is part of Tyynilä’s ideology to turn obligatory systems in to ways to enrich the cityscape. “The stormwater pilot has shown us that the synergy works. The same solutions which help combat climate change also enhance the comfort of the residents,” Tyynilä states.
Colourful eco-homes are being built on Taidemaalarinkatu street
The architects at Sweco participated in the planning of the project at Kuninkaantammi and the checking of the implementability of the zoning and also won the TA-Yhtiöt invitational architectural competition.
“We designed a right-of-occupancy apartment block with 67 flats combining both high-rise buildings and terraced houses with slanted roof profiles. The profiles enabled ceiling heights of up to 6 metres and lofts,” says Sweco architect Anne Lehtinen. “It is very important to us to design homes which are functional, bright and spacious without any wasted space.”
The ecological choices stipulated by the zoning were emphasised in the architectural design of Taidemaalarinkatu street. “Electrical devices and lighting systems are energy-efficient, and some of the buildings’ electricity is produced by the solar panels on the roofs,” Lehtinen says. Attention has also been paid to heat recovery solutions and apartment ventilation.
The masonry facade of the residential block follows the curved design of Taidemaalarinkatu street. The result is colourful and multifaceted just as the zoning dictates. “We used almost 20 different plaster colours on the street’s side!” Lehtinen says. On the yard’s side, there is a different world, where the walls plastered in shades of blue accentuate the fresh and calming atmosphere of the rain garden. “We have also used wood cladding in the courtyard and for the balconies. Using wood for construction is always a preferable choice from a climate standpoint.”
Architecture changes along with energy solutions
Combatting climate change and the energy transition have an increasing effect on architectural design. Legislation guides the design process the most, but Anne Lehtinen believes that in the future architects will have many other opportunities to advance in energy matters.
“The most important thing in city and complementary construction is placing the building on the plot in such a way that it can either be protected from the heat or opened to it. After this, the same idea is continued using smaller means, such as the correct choice of windows and the placement of balconies. Suitable temperatures are ensured using simulations.”
According to Lehtinen, in the future even more emphasis will be placed on construction techniques and materials as well as energy efficiency. “For example, better ways for utilising demolition waste are needed.”
The slow move from passive to active houses in city construction can also be seen in architectural design. “Properties can already produce some of their required energy themselves and in the future sharing locally produced renewable energy with other properties and the national network will become even more common,” Lehtinen says.