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Determined to build Oslo's first passive building, Stein Stocknes bravely faced the many challenges involved, with insulation playing a vital role.

*(ro-en) project_rw_responsible*

Gjerdrums vei 19,
Pb 4215 Nydalen,
NO - 0401 OSLO

Phone: +47 22 02 40 00

*(ro-en) project_developer*

Stein Stoknes

*(ro-en) project_contractor*

Jo Toftdal

*(ro-en) project_architect*

Ratio arkitekter, Sivilarkitekt Stein Stoknes MNAL

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In 2007 Stein Stoknes faced a multifaceted challenge  - to build Oslo's first passive home with a carport and outbuilding. The aim was to develop a holistic energy and climate-efficient structural design for a freestanding home using solid wood as a building material.

"The major challenge was to develop a solution focusing purely on solid wood as the structural element, using the thinnest possible load-bearing cross-sections. This had to be combined with a layer of insulation to avoid thermal bridges and achieve the most cost-effective, space-saving and energy-efficient solutions," explains Stein Stoknes of FutureBuilt.

Environmental consideration

At the time, Stein only knew of ROCKWOOL FLEXSYSTEM as a test product, and had no experience working with it. It didn't take long, however, before he was convinced that FLEXSYSTEM was the perfect solution for the 500 m2 construction project at Skøyen in Oslo. From the outset he had decided to construct the building using solid wood with a lightweight structure, for the sake of the environment and the climate, and therefore chose 35 cm thick FLEXSYSTEM batts for the walls.

"I was very satisfied with what the product had to offer. It was possible to achieve the desired energy reduction, and FLEXSYSTEM was very flexible to work with. The product was much easier to adapt to the building's angled walls," explains Stein Stoknes.

75% energy reduction

With balanced ventilation, heat recovery and solar collectors to provide hot water and heating, the passive building uses 75% less energy than a normal home. FLEXSYSTEM also played a key role, achieving U values of 0.09 W/m2 K for the exterior walls, 0.07 W/m2 K for the floors, and 0.08 W/m2 K for the roof, while the doors and windows average 0.63 W/m2 K.

"In order to protect the environment and limit climate change, there is no doubt we will see more and more projects in future which utilise this lightweight building construction model," says Stein Stoknes.


"I was very satisfied with what the product had to offer. It was possible to achieve the desired energy reduction, andFLEXSYSTEM was very flexible to work with."Architect and developer, Stein Stoknes, FutureBuilt.