While installing state-of-the-art technology is standard procedure in today’s churches, some require more customization to achieve that optimal lighting and sound quality.

The Co-Cathedral of the Sacred Heart in Houston— built in European liturgical style— is a case in point. The $40 million structure is a new landmark in downtown Houston and home to the Roman Catholic Archdiocese for the Galveston and Houston, Texas, area.

With cast-in-place concrete walls that are 80 to 120 feet high- and one-foot thick- interrupted by stained glass windows and lighted artistic elements, the sanctuary posed unique challenges to achieve good sight and sound quality for worshipers. There were wiring issues, lighting difficulties and acoustical concerns- all to be explained in detail here. Sample challenges included:

Wiring
– Adding extensive wiring when 1-ft. thick concrete walls were poured two years before.

Lighting
– Accenting the altar, choir and sculptures without stained-glass glare.

Acoustics
– Restricting urban noise and enhancing liturgical voices in a space that can hold a three-story building.

Nothing about building this 32,000-SF church was standard. The majority of today’s technology on the market for churches is designed for congregations wanting stage production-quality audio-visual, complete with big screens for closed-circuit video and speakers for singers and musicians or praise bands. Worshipers sit in tiered seating and see and hear concert-quality worship services from start to finish.

A Catholic church— indeed a cathedral— is different.

An Old-World Design
The Cathedral has a European design. From the outside, its statuesque silhouette cuts across the Texas sky. Its heaven-pointing vertical stance is due to its impressively high exterior walls, topped by an 80,000-pound copper-clad dome. Some 73,000 square feet of Indiana limestone cover the walls. The gabled roof is made of zinc panels.

Nearby, a bell tower complements the cathedral. A carillon of 23 bells was fabricated by the Royal Eijsbouts Company in Holland, the world’s largest bell foundry. The bells of all sizes were installed 113 feet up inside the 137-foot tower. Four of the largest bells are free swinging, and the other 19 are stationary, but the entire mechanism is computer controlled and is even accessible via the Internet.

Inside, the sanctuary seats 1,820 and is in the shape of a cross. The long, narrow dimension of the sanctuary and its flat-floored pew arrangement meant special considerations so every seat would have unrestricted sitelines.

Besides the aesthetics, the job called for 8,000 cubic yards of concrete. That’s enough to cover three football fields 18” deep. Basically, this building has a massive concrete shell and the technical subcontractors were called in to give it the functional ambiance of a sacred space for thousands of worshipers.

True to the nature of liturgical worship, the spoken word is a key component of traditional Catholic gatherings observing the Latin rite. The bishop is the predominant figure, leading in spoken greetings, prayers, scripture readings, responses, chants, singing, the communion and the homily. Services take on a warm and solemn dignity. Music is more traditional— featuring an organist and sometimes a choir. And lighting is for traditional seating while parishioners observe the holy procession, communion, ceremonial scripture reading, and other elements of the Mass.

Sophisticated lighting and sound provisions were essential. Achieving the technical needs of the Cathedral required “one-of-a-kind” architecture and construction. We frequently drew upon the crew for innovations because of the unique properties of this project.

Wiring
All told, 256,000 linear feet of wiring went into the cathedral. That’s 48 miles long— much more than you’d typically expect in a sanctuary. We used high-voltage and low-voltage electrical, along with the signal wiring for controls and the HVAC.

To ensure superior electrical installations, the designers and contractors began discussing wiring two years before the technical equipment was installed. This required plan management and collaboration with technical subcontractors and product manufacturers. For most projects, you’d build the structure and worry about the audio system on the backside, but here we had to have plenty of foresight.

The design of the building called for concrete structural walls with cement plaster applied directly to the concrete. This left no chase space for the mechanical or electrical infrastructure. Because of this all conduits had to be placed inside the concrete walls. This required knowing where the electrical device was going before the walls were formed and poured. To meet the demand, however, every single conduit and speaker space was drawn into the plan and elevation views early on.

Pouring concrete is what I’d call a violent activity. Concrete also doesn’t allow for flexibility. When it’s poured, the space is determined and not even an 1/8th inch variance is possible. Outlets can get displaced. It may not be rocket science, but it occurred to us that ordinary everyday Styrofoam could be plugged into the walls as they were formed to reserve space for outlets. When contractors were working from tall scaffolding, with framework for the concrete pours, we were carving and inputting one-foot-thick Styrofoam all along the way.
Since the pipes were already installed, once the walls set and the plaster was applied inside, we simply removed the Styrofoam with knives and added junction boxes–ready for wiring down the road. This aided the inclusion of broadcast links to the walls’ exteriors, too. Video production capabilities were also included for closed-circuit communication between the organist and choir director.

As you would expect, some designers were reluctant to provide specifications two years prior to installment because technology changes so quickly. What is modeled that far in advance could easily change in 24 months.

Acoustics
The sacred intimacy felt in the Cathedral is due in no small part to the exceptional acoustics built into the structure. The default acoustics would obviously be cavernous. Concrete, marble, plaster and glass make the prospect of silence with God virtually impossible, but this holy place possesses a spiritual quietness.

Concrete takes in sounds and can cause distracting reverberation. Car horns, passing airplanes, sirens could all threaten the desired quiet that allows reflective worship. Steel structures-common for most other churches built today-minimize this acoustic concern.

Yet, the desired acoustics needed precision to give excellent sound qualities for the words of the priest or melodic sounds coming from the choir and the soon to be installed 5,600-pipe organ.

To address these concerns, we made it a priority to be wise about the interior wall surfaces. While we couldn’t control many ornate aspects of the beautiful sanctuary’s furnishings, we could pay attention to the plaster.

Pyrok Acoustement sound-sensitive plaster was used in the dome and on walls to dampen sound and reduce echo and vibration. This brand combines an excellent plaster finish with the high quality sound absorption needed for such a large space.

Another obvious choice to ensure stellar acoustics was the speaker system. AXYS Intellivox from Duran Audio, The Netherlands, provided the speakers we needed. They are designed specifically for superior voice quality output. The technology is ideal for voice in a flat sanctuary.

The real selling point was the Intellivox system with digitally “steerable” loudspeakers. Technicians came on site to determine the dimensions of the invisible plane that makes up the listening audience’s ears. Other more traditional speakers push sound out and, because of reverberation, the listener will hear anything and everything. However, the steerable Intellivox speakers allow us to point the sound directly at the listener and avoid any reverberating wash.

Being “steerable,” the speakers were aimed with a technical exactness by technicians after installation. This cutting-edge technology uses computer-controlled precision to optimize the width and height of the sounds waves.

The dimensions of the speakers are also unique. They are 18 feet tall by 4 inches wide, obviously very vertical and ideal for audio aimed at the front row and the back row. We installed six speakers total— all surface-mounted on concrete with custom color-matched panels blending seamlessly into the walls.

In a word, the speakers are aimed at the ears of the people to be seated in the pews. It creates an impeccable acoustical experience for such a wide-open space.

Lighting
Two hundred lights were installed, which might seem excessive for a general seating arrangement of the sanctuary, but we had some beautiful worship art elements to highlight, too. There’s too many to describe here, but the most profound and moving are the Immaculate Conception of Mary and the Sacred Heart of Jesus statues, each about 12-feet high and weighing 13,000 pounds. The sculptures were quarried and custom-crafted by Italian artisan.

Then there are the cathedral’s stained-glass windows. The light they bring in is simply glorious. The images they offer remind worshipers of the legacy of faith stretching back to the life of Christ and the early church fathers and holy saints. The dome itself features 12 windows, each depicting one of the 12 disciples.

Accenting each wall are large rose windows 15 feet in diameter, another element reminiscent of the cathedrals of old. And while those holy figures may seem somewhat far from us in time, and in proximity from the marble floor below, a stained-glass depiction of the Holy Spirit in the form of a dove seems to effortlessly hover horizontally in the dome area, just above where the majority of the 1,820 seated worshipers pray.

Even more stirring is the altar where you face the Sacred Heart of Jesus crucifix made of Italian wood. Tradesmen used a striking red marble in the altar.

We used mostly Halogen lighting. Accent lighting with metal halide lamps was the exception for the altar, the baptismal font and stained glass where powerful lumination in smaller spaces was required.

One special challenge was the stained glass of the Holy Spirit that was suspended just beneath the huge dome, 110 feet up from the floor. The designer wanted it to “glow”, and yet replacing any bulb would be impossible.
We decided to install an LED light with a warranty of providing 53,000 hours. We figured that would keep the glow going for some 30 years under typical circumstances, and therefore not require a crane to change a bulb every few years.

The cathedral is a living representation of “Christ among us.” City officials, church leaders and parishioners alike hail its construction and presence as a marvel— a sort of miracle— for the eyes and ears, as well as the soul.

Customized and sophisticated technology has a lot to do with that.
The key lesson I learned— besides being educated about cutting-edge speaker systems and how to wire a big cathedral— was to do the advanced planning when it comes to technology.

At multiple points along the way we had to tell the acousticians to stop holding out for the next new “techno-vation” and say it’s time to decide on what product is going inside.

Collaboration and team work obviously are mandatory for a job this big. We were blessed to have a great team of church representatives, Linbeck managers, and consultant technicians to make this vision a reality.