Saint Hugo of the Hills Catholic Church

Saint Hugo of the Hills Catholic Church in Bloomfield Hills, Michigan engaged Memtech Acoustics to address reverberation in its main worship space and entrance. In a worship space, long reverberation reduces speech clarity and raises background noise.

Challenge

The worship space is a large room with a sloping drywall ceiling reaching roughly 39 feet at its peak, tiled floors, wooden benches, and stone walls with few interrupting features. Surfaces like these reflect nearly all sound energy back into the room, and the report linked them to the poor speech clarity and elevated background noise the church had experienced.

Solution

Memtech Acoustics measured reverberation time (RT60) and speech clarity (C50) in both rooms under unoccupied conditions, recording at four microphone positions in the worship space and two in the entrance across octave bands from 125 to 4,000 Hz. Reverberation reached 3.4 seconds in the worship space and 2.7 seconds in the entrance, with C50 values of 4.7 dB and 1.6 dB. The measurements confirmed that the smooth stone, tile, and drywall surfaces were the primary cause.

Because covering the windows and doors was not a viable option and treatment had to preserve the room's aesthetics and function, treatment was concentrated on the ceiling. Using a parametric model built from the measured data and the absorption performance of the specified materials, Memtech sized the coverage to the target rather than distributing panels arbitrarily. The worship-space design specified 44 four-foot-square, four-inch-thick open-cell foam panels rated NRC 1.04, with the thickness selected to absorb the low-frequency energy that dominated the measurements. The entrance was addressed with a companion two-inch panel layout.

Results

The engineered design was modeled to bring the worship space to a 2.5 second reverberation target and the entrance to 1.5 seconds. The design has not been installed, so the modeled results have not been confirmed by measurement.