Architect: Kjær & Richter, Denmark

Elementary school reduces CO2 levels with ventilation ceilings

Documented improvement of indoor air quality and acoustics

Fresh air is essential for children's well-being and ability to learn. At the city school of Elsinore, Denmark, pre-renovation measurements showed CO2 levels reaching up to 3000ppm during large parts of the day. That is three times the recommended levels. In addition, the acoustic enviroment was far from the required levels of 0.6seconds in reverberation time. So the listed school building from 1880 was in need of an extensive renovation.

But how do you modernise ventilation systems in buildings from 1880 without losing floor height? The solution was found by combining acoustical ceilings and ventilation system into one solution - using so-called ventilation ceilings with diffuse ventilation. This solution saves space and building and maintenance costs.  

School reduces CO2 level by 66%

  • The CO2 concentration is reduced by 66% with the renovation (where acoustic gypsum ventilation ceilings were the new solution)
    From 3,000 ppm to the recommended 1,000 ppm

  • Reverberation is reduced by approx. 50%
    From approx. 1 second to approx. 0.5 seconds

  • 20% lower energy consumption
    Because the ventilation system can be downsized thanks to the acoustic ventilation ceilings from Knauf DANOLINE

A ceiling solution that combines aesthetics with acoustics and ventilation

The solution to the challenges with the indoor climate and the noise nuisance was the ventilation ceilings from Knauf DANOLINE. The gypsum ceiling panels combine aesthetics with acoustics and ventilation because of the the design and function. The panels are demountable, so it is easy to service ventilation, lights or other hidden installations.  

All the panels are perforated with holes which allow fresh air from the ventilation to penetrate down through the ceiling. This provides an even and comfortable exchange of air throughout the room. The holes also significantly improve the acoustics, and because the holes go all the way to the edge of the panel, they also create a nice and uniform look. 

The functional benefits are also reinforced by considerations for aesthetics and long-lasting solutions: “We decided to go with gypsum ceilings for aesthetical reasons – as it is more in line with buildings from the 1880s than other ceilings available. And because it is our experience that gypsum simply lasts longer in schools”
Hanne Pedersen, Architect, Project Manager & Construction Economist, Kjær & Richter
  • Skolen i Bymidten by Kjær & Richter, Denmark Belgravia Unity
  • Skolen i Bymidten by Kjær & Richter, Denmark Belgravia Unity
  • When integrating ventilation with the acoustical ceiling, you can make the ceiling without air inlets. The fixtures in the ceiling are kept at a minimum - only the exhaust vents are necessary. Learn more about how ventilation ceilings work: Ventilation & acoustics
  • Skolen i Bymidten by Kjær & Richter, Denmark Belgravia Unity

CO2 levels cut by two thirds in comparison to before renovation

The classrooms at the school are renovated using Knauf DANOLINE's ventilation ceiling Belgravia Unity 3. The improvement of indoor air quality is documented with a post-renovation report, made by an independent institute for the municipality of Elsinore. The report shows that the CO2 levels have dropped from the previous 3000ppm down to the recommended 1000 ppm.

Sound treatment according to recommendations

Along with better indoor air quality for the school children and their teachers, the ventilation ceilings also ensure a better acoustic enviroment. The report documents that the reverberation time in the classrooms is reduced to 0.4-0.5 seconds, which is just at the levels recommeded by the building regulations. 


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Architectural benefits

In addition to the significant indoor climate improvement, our acoustic ventilation ceilings also offer important construction advantages. By leading fresh air directly into the cavity, the architects at Kjær & Richter could:

  • Save ventilation inlets
  • Avoid pipe crossing and save construction height
  • Reduce the diameter of exaust pipe in some places down to 350 mm 
"Our objective was to minimise building height while retaining as much of the original volume as possible. That is why we worked with ventilation ceilings."
Hanne Pedersen, Architect, Project Manager & Construction Economist, Kjær & Richter

An aesthetic and recyclable solution

  • A recyclable material
    Gypsum can be recycled indefinitely, and today we use up to 30% recycled gypsum in our solutions

  • Fewer ventilation installations
    The unique design minimizes the need for ventilation installations, and the remaining installations can be hidden behind the ceiling panels 

  • Lower installation height
    Because the need for ventilation pipes are smaller, as well as the installation height also becomes correspondingly

  • Can be repainted
    Ceiling panels are pre-painted when being produced, but if they at some point need repainting, you can easily do it - without compromising the acoustics or the ventilation