‘Best new school building 2022’ is much more than just a school

To understand how Vrå Børne- og Kulturhus ended up with its design and look, you need to lift your eyes and look at the area within which the building is situated.

“The outdoor areas have really played a major role in our thoughts about the school and the design concept. We were allocated a large plot where we were inspired by the landscape, which encompasses several woods in geometric shapes. The client also emphasised that the building had to support lots of outdoor education. This gave us the idea that we should not only make a new school – but also a new forest, and put the school inside that forest,” explains Kathrine Hegner Stærmose.

At the time of writing, the new forest is no more than bare trunks, but the idea is that the trees will play a major role in the long term, not only for the outdoor education, but also for the indoor climate in the buildings.

“We reached the conclusion that we wanted to use the forest to provide both good indoor and outdoor climate. Trees are so amazing on hot summer days, because there is a big temperature difference between sun and shade,” says Hanne Tine Ring Hansen.

The challenge for the consultant team has been that it is difficult to calculate, simulate and document the effect of trees on the indoor climate. A project with funding from Realdania will therefore investigate how planted trees affect the light in the building – whether you can use trees for sun shading without negatively affecting natural lighting.

The new forest is just one of the many passive solutions in play in Vrå Børne- og Kulturhus. Hanne Tine Ring Hansen notes that the indoor climate is a recurring headache in school buildings.

“Before we even put windows in a school building, it’s too hot. This is due to the number of people per square meter. Even though they’re children, they emit a lot of heat. An adult emits 100 Watts just when sitting still. So if we put 20-30 people in a room, it gets really hot,” she explains.

“The way this has been addressed to date is by installing mechanical ventilation systems and external solar shading on the buildings. With this project, we wanted to see if we could take a different path. Fortunately our client, Hjørring Municipality, was bold and supported our idea.”

The solution was to have a central room with a modest-sized ventilation system that distributes air into the three ‘fingers’ of the building – or the three ‘phase houses’, as they are also known.

“Just before the wall of the classrooms, the air ends up in an sealed chamber, where it comes into contact with the concrete and is cooled down. The air is then distributed evenly in the classroom via Troldtekt ventilation ceilings, in which some of the acoustic panels are permeable, so that the air can seep through. This leads to a good distribution of air without causing draughts,” says Hanne Tine Ring Hansen.

She notes that the solution has very high ventilation efficiency, because the warm air in the classroom automatically rises upwards and ensures efficient air exchange. The solution is estimated to be one and a half times more efficient than traditional ventilation, and the Troldtekt ventilation ceiling also functions as an acoustic ceiling with a visually smooth surface and no visible blower fixtures.

Wood and cement give Troldtekt acoustic panels their unique properties, and Vrå Børne- og Kulturhus also pairs these two raw materials, notes Kathrine Hegner Stærmose:

“We have wooden structures in the ‘heart room’ of the building and on our exterior walls. We actually wanted to build the whole school using wood, but it ended up not being feasible in the phase houses,” she says.

Hanne Tine Ring Hansen adds:

“We chose to make the load-bearing structures – the deck – in situ cast concrete, to ensure both a flat and thin ceiling. In our comparisons between prefabricated elements and in situ cast elements, the latter very often win in terms of environmental impact. In addition to flat ceilings, we don’t bring in a lot of steel beams either. Apart from offering flexible construction, the concrete in the ceilings also becomes a significant part of the thermal mass, helping to ensure a good indoor climate,” she explains.

As the public acclaim and the ‘Best new school building of the year’ award indicate, Vrå Børne- og Kulturhus has been given an overwhelming and positive reception so far.

“At the official opening, the client reported that they had not received any complaints after building users moved in. This is quite unusual. But at AART we are not content to just hope and believe. We therefore revisit our buildings to investigate what the experience is like, after users have had time to get used to and begin using them,” says Kathrine Hegner Stærmose.

She expects the results of the investigation to be ready by the end of 2023.

Read more and see more photos from Vrå Børne- og Kulturhus