The Janus Arena was opened in Lahti

In December, a new tennis and badminton hall with low energy consumption was opened in Lahti (Heinlammintie 64). The hall has been named after its manufacturing company, Janus Ltd., which has signed a marketing contract with Lahden Tennis- ja Squashkeskus Ltd. 

The hall is unstaffed, with two tennis and four badminton courts, and it can be accessed with a door code provided in conjunction with a booking. The Janus Arena widens the range of opportunities for the growing needs of enthusiasts of both sports in the Lahti area.

A durable structure guarantees a long life span

The Finnish Janus Arena has an area is 1,991 m2 (width 37m, length 53.8 m, height in the middle of the hall 9.1 m). The hall’s CE-marked frame structure is made of hot dip-galvanised steel and it has been designed to withstand local wind and snow loads. The inner and outer roof covering of the hall is made of durable PVC fabric. Janus Ltd. gives a 10-year guarantee for both the frame and the PVC roof covering. The hall’s frame structure is excellently suited to sports requirements since there are no restrictive vertical beams. This enables efficient use of the entire premises. The hall’s lighting has been designed for tennis and badminton. New social premises have also been built in conjunction with the hall.  

Energy efficiency, flexibility and moderate construction costs as assets

Janus Ltd. has built halls for a variety of sports and user experiences have been positive. In particular, the low energy consumption of the halls has received praise. Lastly, we can mention the Mehtimäki tennis and golf hall in Joensuu, which was completed in 2013. The hall’s area is 2,601 m2 (volume 17,480 m3) and it is heated with district heat. During the 12-month monitoring period, the hall’s energy consumption was 54.3 MWh (below 21 kWh/m2), including water. It could be compared with a passive house, where the energy consumption is defined by the Technical Research Centre of Finland as follows: ‘A passive house requires a quarter of the energy that current new houses consume for heating the rooms, i.e. 20 kWh per square metre in Southern Finland and 30 kWh/m2 in Lapland.’ (Source: In other words, the Joensuu tennis hall nearly met the passive house heat generation requirements for Southern Finland.

The heating system of the Janus Arena, built in Lahti, has been realised with three air-source heat pumps, meaning that energy consumption is expected to be even lower. ‘I dare claim that this hall has the lowest energy consumption in Finland,’ says Taisto Virtanen from Janus Ltd.  

Flexibility and energy efficiency, combined with the moderate construction costs of the hall, offer a cost-effective solution for practicing a variety of sports all year round.

The Janus Arena - Key facts

Construction time approximately three months, starting from the completion of the foundations.