Grönbo is building the wooden houses of the future

Organic wooden houses that are projected in 5D, are mounted in an efficient building system and are both energy-efficient and quiet to live in. This is how the apartment buildings that are currently being built in Skellefteå by Grönbo are described; the construction company that has got a taste of wood.

At a time when electricity prices are rising and environmental requirements are tightening, it is becoming increasingly important to choose building materials that are energy-efficient and environmentally friendly. Grönbo is one of the construction companies that invests in building wooden villas, terraced houses and apartment buildings.

- Our energy-efficient apartment buildings have a frame of 90 percent wood and we work hard to find materials that are as non-toxic as possible. It is good both for the residents' health and for the environment, says Anders Eriksson, technical manager at Grönbo.

Grönbo has previously built wooden apartment buildings on Lusthusbacken in Piteå. Construction of five apartment buildings in Södra Karlgård in Skellefteå is currently underway. The five-storey buildings will together accommodate 57 condominiums, when construction is completed at the end of 2019. Just as with the wooden houses in Piteå, it is Masonite Beams that has delivered the frame.

- Our strong construction-glued light joists and joists have an I-profile which means that less raw material is used compared to solid wooden constructions. In addition, sound waves and cold bridges are minimized, which means a quieter living environment, reduced heat leakage and reduced housing costs, says Tommy Persson, technical manager at Masonite Beams.

"Together we have managed to create a unique construction"

Masonite Beams and Grönbo have also worked purposefully to create as quiet a living environment as possible in the wooden houses. There, acoustics expert Klas Hagberg at Acouwood has played a key role.

- Together, we have succeeded in creating a unique construction with an extremely quiet living environment that is acoustically better than most houses - regardless of frame system. A large part of the explanation lies in Masonite Beam's I-joists and its collaboration with other parts of the system, while we have made point efforts to steer the system in the right acoustic direction with well-thought-out total solutions for floors, walls and not least nodes. Masonite Beams and Grönbo have aimed far beyond the minimum requirements for sound and have developed a unique solution that is a leader in the industry, says Klas Hagberg.

But it is not just the end product, ie the energy-efficient and quiet wooden house, that is unique. Both design and construction have been cast in the shape of the future through Masonite Beam's MFB building system for apartment buildings. In the current project with Grönbo, this state-of-the-art construction system has meant a completely new accuracy in time and cost calculations, less waste material and an efficient and weather-protected construction process. Tommy Persson explains:

- The design is done in 5D, where time and cost each constitute "D". Simply explained, this means that we start from an advanced 3D drawing that is linked to synchronized computer programs for time and cost. If you only make a small adjustment in the 3D drawing, such as moving a window, the programs directly calculate how the cost and possibly the installation time change. The bottom line is that we can model the house in the computer, cut to all parts in advance and get an almost exact time and cost calculation, he says and continues:

- When it comes to the construction itself, all assembly takes place under a large tent so that we can build tight and dry. The construction process is almost similar to a small factory, like an industrial building stuck in a field. The model is "lean", the ideology that has its origins in the automotive industry. The result is an efficient flow in the construction process that maximizes the customer's needs, reduces waste and provides the right conditions to keep to the schedule. Grönbo has recently established a house factory in Norsjö in Västerbotten, an investment that will triple the annual capacity of wooden apartment buildings. As before, the houses will be built according to Masonite Beam's MFB building system.

- The big advantage of Masonite Beam's MFB building system is the possibility of preparations which means that we basically only have the actual assembly left when we get to the construction site. It raises both the pace of construction and the quality. With our new factory, we will increase our competitiveness on the rental side. Right now we are working on and planning a couple of areas in the Stockholm area, says Anders Eriksson.