O'Fallon, Illinois

Acoustical Considerations for St. Clare of Assisi's New Church (Part I)

March 27, 2009

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Collaboration and teamwork have been mentioned often in other articles in this series by the pastor, liturgical design consultant, and architect. These factors are important in concept, as they set the tone for the professional relationships and interactions among team members, and then in practice, as the design process proceeds and bears fruit. The design team for St. Clare, as for most church building projects, was made up of professionals in architecture and engineering, supplemented by others, including a liturgical design consultant and acoustician. Ideally, and in this particular case, the design team collaborated with the church staff, building committee, and other parish members, mainly through the architect, who served as liaison between the professional design team and the parish team.

My allusion above to the acoustician as a somewhat distinct entity is intentional;  it is meant to suggest that the acoustician plays a slightly different role compared with the architect and engineers (the “A & E team”). Architects routinely engage engineers for building projects including, most commonly, structural, View of sloping choir space.electrical, and mechanical engineers, often from the same multidisciplinary engineering firm. Very few engineering firms, however, have acoustical engineers on their staff. In fact, the term acoustical “engineer” in reference to those who work on church building projects is somewhat of a misnomer, since most acousticians are not trained engineers and fewer still are licensed Professional Engineers. This, in part, is because architectural acoustics does not involve life safety or code requirements, so licensing is not required. Another factor is that, in practice, acoustical design for liturgical space is a highly subjective discipline: it is truly a mix of art, architecture, physics, and experience.

With that prelude, I can elaborate on Fr. Jim Deiters' comments on the formation of the design team, with the acoustician brought on board near the beginning of the project. This is advisable because acoustical factors can actually “shape” the building, especially with regard to fundamental building geometry, height, physical volume, surface orientations, etc. (Note that other factors, such a materials and finishes, are less fundamental to the basic design and are considered later in the design process.) With the demographic projections for the O’Fallon, Illinois area, the new St. Clare Catholic Church was to be designed with 1100 seats. This led to the consideration of relevant liturgical factors, and so the architectural design task involved collaboration with the liturgical design consultant in evaluating seating configurations to situate 1100 people, not too distant from the altar, and with good sightlines, and also with the acoustical consultant to evaluate hearing conditions throughout the assembly seating area and sanctuary. An 1100-seat assembly space requires adequate climate control, and collaboration between the mechanical engineer and acoustician was initiated to begin design for HVAC noise control.

Design for the music ministry area was also considered very early in the design process, since the music ministry and its location involve liturgical, acoustical, and visual factors. This invited collaboration among the architect, liturgical design consultant, acoustician, and St. Clare’s pastoral musicians to address the delicate and seemingly conflicting requirements for the musicians to be both members of and ministers to the assembly.

Sister Carolyn."The placement of the choir should show the choir members’ presence as a part of the worshiping community, yet serving in a unique way. Acoustical considerations will also play a role in determining the best location for the choir." (Sing to The Lord §98)

The location of the music ministry can be a key factor in shaping the floor plan (it often, in fact, influences the entire seating arrangement) and this might be further complicated by the presence of a pipe organ or the hope for one in the future, as was the case at St. Clare. As the design progressed it became evident that it would not be possible to have a pipe organ installed as a part of the initial building project, so a variety of options were considered for the future, including pipe organs, used organs, electronic, and hybrid (pipe/electronic) organs. The design of the church made real provisions for a future pipe organ. As of this writing, a three-manual electronic organ has been installed with the hopes of adding real pipes in the future.

Continue to Part II of this 2-part article.

Photo credit: Dennis Fleisher

Dennis Fleisher earned a Ph.D. in Physics/Acoustics and Music from the University of Rochester/Eastman School of Music.  He is principal of MuSonics, Grand Rapids, Michigan.


Acoustical Considerations for St. Clare of Assisi's New Church (Part II)
Acoustics for Liturgy
Church Acousticians and Their Roles in Church Building and Renovation Projects (Part I and Part II)
Room Acoustics: Its Significance in  Sacred Space and Liturgy

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