Smart ventilation in high-rise block cut the costs

Kajalen, Kalmar

The housing company Kalmarhem was struggling with energy issues when plans were under way for the construction of Kalmar’s tallest building, Kajalen. The operational and service costs for the ventilation system would be considerable due to the size of the building. Swegon, which has extensive experience of upgrading and modernising ventilation systems in apartment buildings, was awarded the contract.

Inaugurated in 2017, Kajalen stands at 15 storeys, making it the tallest apartment building in Kalmar. The building houses 86 apartments of varying sizes.

86 apartments – 86 different needs

Kajalen had to be built in an energy-efficient way to meet rigorous energy saving requirements. It was therefore necessary to provide an end-to-end solution for demand-controlled air flows that was not only energy-efficient but also simple to monitor, maintain and service. Ventilation management and control was a particularly critical factor. The considerable amount of time and administration that it would take for one technician to check the air inside the 86 apartments was something to be avoided.

Think of the big picture. And think smart

Swegon delivered a system that analyses and ventilates each room exactly as much as needed. The flow can therefore be kept to a minimum when the apartment is unoccupied. The centrally positioned unit allows fresh air to be distributed almost silently in the residential setting. The diffuser is designed to produce good air circulation even at low flow rates, and sound levels are kept low at higher flow rates.

The system is designed to facilitate individual control of the features for each apartment. Features such as temperature, air flows, odours and radon. Instantaneous readout or recording of trends over periods of time can be useful for maintenance, troubleshooting or as data in discussions with tenants.

And the crucial question, if the ventilation system could be controlled outside the apartments, was answered by installing the technical equipment boxes in the stairwell outside each apartment. The box allows the landlord to control the apartment’s air flow without having to enter the apartment.

Tremendous savings potential

In a building with lots of apartments where occupancy varies, there is huge potential for making savings. As much as 80% of fan electricity and 40% of heating/cooling energy can be saved with demand-controlled ventilation compared with a system that maintains a constant air flow. The turnkey system that property owner Kalmarhem had installed not only resulted in reduced energy costs but lower management costs too.

It also felt reassuring for us to choose a renowned supplier that could deliver a complete system. Having a clear view of every stage of the chain means they can fix any operational faults without intermediaries. That feels reassuring. Patrik Håkansson, Operations Manager at Kalmarhem