Dome-shaped pavilion made from Kerto LVL

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Dome of Visions 3.0

​Aarhus is the European Capital of Culture in 2017 and for this occasion, a huge transparent dome of glue-laminated timber will serve as the Aarhus municipal pavilion for building culture.

The dome-shaped building, called Dome of Visions, will throughout 2017 give inspiration for new ways of building and living. At the same time, the building will function as a modern community hall, which will make room for conferences and debates on the sustainable cities and buildings of the future.

Besides being a modern community hall, Dome of Visions 3.0 is the third dome in a series of visionary and experimental constructions.

A modern community hall
Slim and elegant grid construction

The architect Kristoffer Tejlgaard focuses on sustainability and to him the natural choice of building material is wood. For that reason as much of the Dome as possible have been built with wood. For example, this applies to the spectacular grid construction that forms the dome and where Kerto® LVL (Laminated Veneer Lumber) proved to be the optimal building material.

Kerto LVL is a central element in this third edition's improved dome design.

The dome is an improved version of two previous dome experiments. The first placed in both Aarhus and Copenhagen and the second placed in Stockholm. In this third version, the dome has grown to be 10.5 meters tall and with a cross section of 24 meters, which forms a room of 450 square meters. It is about 100 m2 larger than versions 1 and 2.

Load bearing grid of Kerto® LVL

The facade of the dome is transparent, strong and built on a wooden grid of beams from sustainable and PEFC certified Kerto LVL, and assembled with invisible and embedded steel brackets.

The grid construction of triangular shapes obtain high strength and stability and rhombus shaped sheets ensure high material utilization and low waste of the polycarbonate plastic facade.

The dome rest on six large pieces of curved glulam that forms a circular platform. This platform rests on a screw foundation consisting of two to three meter deep screws divided into 46 points anchored in the ground. This ensures solid foundation without extensive excavation work.

Kerto ensures slim and elegant grid construction

A new system of curved wooden beams, composed of 21 mm strips of Kerto LVL (laminated Veneer Lumber), made it possible to minimize the amount of steel while achieving both a sleek and elegant grid construction.

Using curved wooden beams, the brackets for the dome's focal points were cut as stars in a five-millimeter steel plate.

"With the custom-made Kerto beams it was possible to avoid complicated and costly welded brackets used in earlier versions of Dome of Vision," says Kristoffer Tejlgaard.

"A challenge in this system was to mill curved slots for the steel brackets. The solution was to construct each bar from six layers of 21-millimeter Kerto LVL strips. Using a CNC milling machine it was possible to cut a slit for the brackets before the gluing process", Kristoffer Tejlgaard explains.

The dome comprises a total of 588 curved beams, and with 186 different shapes, only a few beams are alike.  Each beam consists of several layers of Kerto LVL strips, and so it was one of the major challenges during development, to handle the large number of cutting files, 2,232 pieces, to be CNC milled and subsequently glued.

Sustainable building material from solar powered factory

According to the architect, wood is the building material that best approaches a sustainable material for construction.

"Wood as a building material has obvious advantages giving sustainability for the building industry. In principle, wood is a material that comes from a solar-powered factory", says Kristoffer Tejlgaard referring to the ability of trees to extract CO2 from the atmosphere and store it as carbon in their trunks, solely by means of solar energy.

Dome of visions

Carbon-bearing wooden structure

The total construction is made of approx. 100 cubic meters of wood, and according to the architect, this store 80 tons of CO2.

"This will save the atmosphere from 100 tons of CO2 compared to a similar building in concrete that would emit about 20 tons of CO2," says Kristoffer Tejlgaard.

Climate screen provides freedom of design

Coated with polycarbonate panels the Kerto dome structure works as both a greenhouse and a weather screen for the inner house. Shielded from wind and rain the dome allow for great freedom in design and choice of materials.

This is utilized to leave the interior wooden house, built from cross laminated timber (CLT), with fully exposed wooden surfaces and a large open terrace that covers the entire roof (a design that would not be possible without the protective dome).

Climate screen provides freedom of design

The many individually adapted and curved Kerto beams were prefabricated and this ensured a fast and efficient building process at the construction site. All parts were prepared at a specialist workshop. Ready to install on site it saved a lot of time and money.

The finished dome is the result of a successful experiment with Kerto LVL, giving Aarhus and the European Capital of Culture a unique place for events in a spectacular wooden building. A building that undoubtedly will provide inspiration for a future with more sustainable and climate-friendly timber construction.