For a year and a half, the Sadan vuoden talo (Century House) construction site has been a visible landmark in the residential area of Pietniemi in Pori. In fact, everyone in Finland will soon be able to follow the design, purchase of materials, and construction of this eco-friendly wood house. A ten-part reality TV series on the construction of Century House is scheduled for October on Yle’s TV 1 and on Yle Areena.
TV producer Juha-Pekka Ristmeri tore down the mildew- damaged brick house his father had built in the 1960s and constructed a healthier wooden house suitable for different sized families in its place. Ristmeri wanted a low-emissions, zero-energy house that would be easy to take care of. The aim is a house made entirely of wood that will last twice as long as the one built by his father.
The neighbourhood around Century House is an eclectic mix of detached and semi-detached houses of various kinds. The city plan placed just one restriction on construction: the new house could only have one storey.
Architect Jukka Koivula, who specialises in wood construction, came up with five proposals. The last one, reminiscent of a triangle-shaped sandwich, was selected. The building is placed alongside the pine trees, shields the courtyard with its form and provides favourable conditions in the Finnish weather. The stand of pine trees on the spacious plot made wood a natural choice for the frame and facade materials.
The Century House was constructed in two ways: the exterior with tongue-and-groove planks and the walls on the inner courtyard with vertical planks. The street sides are more closed off than the courtyard sides.
A frame made from Finnish wood
The owner wanted to avoid his father’s construction mistakes and chose a CLT (Cross-Laminated Timber) frame for the house.
Among the benefits of the prefabricated CLT elements (available in 60, 80 and 100mm sections) are their breathable structure, their ability to even out moisture, their finished inner surfaces and their quick installation time of just over a week. Getting the elements to fit into a triangular home proved to be somewhat of a problem.
A total of 78 element drawings for the frame were made and then delivered to the CLT factory for production. The prefabricated elements were delivered to Pori on two semi-trailer trucks.
The measurements of the numerous sloping angles and the footing caused the most work in the installation phase. The laminated veneer timber roof joists were installed on the wall and ceiling elements and the ventilated outer roof was attached to the lower roof without leaving space for an attic. The ventilation pipes and electrical installations were passed through the beams.
Installers from Kuninkaankylän puurakentajat put together the CLT frame. The external frame (250mm) is the foundation for the eaves, and a layer of wood fibre insulation is tucked under the frame’s 18mm wind barrier.
The CLT installation was relatively quick and precise. Only one element had been angled incorrectly at the factory. The inner surfaces required a little additional sanding at the work site. The end result was good: the surfaces and joints were precise, and there were few cracks and other defects.
Turning the interior into an incubator for ideas
The Century House was built with its entire life cycle in mind, which is why it is designed to accommodate families of different sizes.
The entrance to the house is almost clandestine, through a shed-like structure, and the sauna and the kitchen maintenance door are tucked into the entrance. The emphasis is on the main living areas.
The living room, study and master bedroom are slightly higher than the other spaces. The ceiling slants down towards the courtyard. The living areas have a floorspace of 171 square metres.
The creative profession of the home’s TV producer owner placed its own requirements on design in order to bring the concept of an “idea incubator” to life. This required that attention be paid to the design of lighting and acoustics, peaceful work spaces and suitable building technology. There is also plenty of wall space for screens.
The owner also wanted a bright winter garden, and the resulting greenhouse was connected to the living areas. The wood surfaces of the interior’s CLT elements were left in plain sight without finishing.
The shapes and characters of the windows and glass surfaces vary in accordance with the interior spaces. The street-facing corner of the building was accented, and a triangular bay window was placed in the otherwise uncomplicated western face. The large glass surfaces on the courtyard side open out into views of the beautiful landscape.
The wide skylight lets light into the main living areas and lets those inside admire the canopy of the pine trees. The covering of the terrace was also partially made of glass.
The building is equipped with a heat pump and an air exchange that stores heat. The roof has space for solar panels and a covering of stonecrop grasses.
Project in brief
- Location | Pietniemi, Pori
- Purpose | Residential building
- Constructor/Client | Juha-Pekka Ristmeri
- Architectural Design | Jukka Koivula Architects
- Structural design | Sweco Rakennetekniikka Oy
- Contractor | Dallasforce Oy Ab, Kuninkaankylän puurakentajat Oy
- Electrical design | Sähköasennus R. Myllykoski
- HVAC design | RS LVI and Energiakonsultointi
- Volume | 909 m3
- Year completed | 2017
- Photographs | Raimo Sundelin
- Text | Juha Granath