How is the extension room used

Timber construction in Hasloh

In the first variant, the bell tower stands free next to, in front of or behind the parish hall. With this variant, a major disadvantage emerged: The “bell window” would not correspond to the view of the competitive perspective, as the loud, swinging bells cannot take place within the construction of the community building due to the dynamic loads of the “correct ringing”. The need for three-phase current and the high costs for the bell tower also spoke against the first version.

The second variant that was ultimately chosen is a "simulated ringing" with fixed bells. With this variant, integration into the parish hall is possible both statically and acoustically. In this variant, according to the design, behind a pane of glass, both bells are placed one above the other and visually convey the message “I am a church”. To ring the bell, the hammers are electronically controlled in such a way that swinging is simulated. The conversion is relatively cheap at around € 4000.

As a third variant, an electronic bell is possible, in which the bell tone is generated digitally with loudspeakers. The variant was not investigated further because the existing bells according to the "simulated ringing" variant can still be used.

Simulated ringing - sound generated by striking an electric hammer

Contrary to the well-known swinging, which causes the typical "ringing of the church bell", the bells are not moved when the simulated ringing occurs. They therefore do not introduce any vibrations or dynamic loads into the building. Their charismatic tone is created by striking an electric hammer, which emulates the typical sound rhythm of church bells. On the positive side, in addition to the fact that the bell is no longer swinging, the hammer only needs 220 volts. According to the statement of bell expert Mr Schwarck from Iversen & Dimier, the volume reduction associated with the solution is hardly noticeable to an inexperienced listener. The variant of simulated ringing also proved to be the most cost-effective of all tested.

Ringing without the introduction of dynamic loads

The fact that simulated ringing was chosen benefits the expression of the wood-clad community center. Since the bells do not vibrate, the bell tower can be very small, which is the size envisaged in the competition design. The bell expert also recommended not opening the underside of the bell directly to the square. Instead, the bells are made visible using a window. Sound hatches, which are installed invisibly behind the wooden cladding, can be designed for an adequate sound image. In this way, it is also possible to fine-tune the sound later by adjusting or partially closing it from the inside. A sound-insulated push-in staircase installed near the vestibule makes the bell room accessible for maintenance purposes.

It is planned to insert the bells during the construction phase, i.e. before the façades are closed.