Bright but not hot

When eco-buildings are to be classified it is a requirement that the energy consumption used to cool the property has to be low – while preserving as much of the natural daylight as possible. (see article in Swedish below)


This was the problem which Karl Frisell, head of business unit Stockholm North at Klövern, was presented with when the planning started on Tele2’s new head quarters in Kista – a building with 700 sq.m. glass roof. 

- Being forced to install large external sun shading solutions is for severalreasons a constant dilemma. Then I came in contact with the company MicroShade, which are a relatively large player in Europe but not yet established in Sweden.
Their technology keeps out almost all of the solar irradiance while at the same time letting through the daylight.

A couple of blocks away, Klövern is refurbishing the large commercial building known as ‘Time Building’. At this location the new solution is being installed and Klövern is also moving its own Stockholm North unit to the building. In ballpark figures it is three times the cost of ordinary glass but this is a cost which Karl Frisell predicts will be recouped.

- First and foremost, it will be a maintenance-free solution as opposed the mechanical solar shadings which always break down.

- Also, the cooling systems are dimensioned to handle the solar energy surges when the sun heats the most – something which is relatively rare in our country.
This means that you throw money at incidents that hardly ever occur but thanks to the new glazing we have been able to reduce the dimensions on the cooling system in the Time Building by half.

And since the roof on the Tele2 building does not need to carry the weight of a mechanical solar shading system as well as a lift for maintenance, it was possible to save quite a lot of building material in the construction of the roof.


Karl Frisell also expects the MicroShade solution to contribute to increased revenues.

-       With ordinary glazing there is always space near the window which cannot be used due to the heat produced by direct sunlight. Now, can make a floor plan where furnishing is made possible all the way to the outer wall. To a large real estate owner this turns into many square metres of additional available space for rent.

MicrosShade consists of a thin layer of micro-lamella. When you look at it up close it looks like lots of very small perforated holes. The secret to them is that they are angled in such a way that they provide shade at some angles and allow light in at other. A typical summers day when the sun is at its highest the energy from the sunlight is reduced by up to 90 per cent. During the colder half year when the sun is low in the sky the solar energy is let through the glazing.

-       This means that all glazing is specially made based on calculations on where they will be installed, explains Karl Frisell.

 

Erik Hörnkvist
Fastighetstidningen, no. 3, 2016

25 April 2016