Building a Modern Cathedral: How St. Paul Catholic Church Balanced Historic Design with Contemporary Roof Performance
Introduction
Olathe, the Shawnee Indian word for “beautiful,” is located about 20 miles southwest of downtown Kansas City, Kansas. The city of roughly 150,000 people served as a stop along the historic Oregon-California and Santa Fe trails and was first incorporated in 1857. Olathe experienced huge residential growth following the establishment of Interstate 35 in the 1950s, and they haven’t stopped since.
St. Paul Catholic Church in Olathe needed to expand to meet the needs of a growing congregation. A new church building was designed to evoke the timeless architecture of traditional European cathedrals, complete with soaring cathedral ceilings, intricate rooflines, and carefully crafted architectural details.
While the design delivered the historic appearance the parish envisioned, it also presented modern construction challenges. To achieve the desired aesthetic while simultaneously meeting current building codes and roofing performance requirements, the project team turned to products and a company they knew could handle the intricacies.
Project Challenge
Unlike conventional commercial buildings, the new St. Paul Catholic Church features expansive cathedral ceilings that extend directly beneath the roof structure. Maintaining those dramatic interior spaces required a roofing assembly that could provide continuous insulation, proper ventilation, and long-term moisture management without lowering the ceiling profile.
"Insulation and ventilation are the key to cathedral ceilings," explained Granville Hare, director of preconstruction with installer JR & Co., a nationwide installer with international experience, operating primarily out of Missouri, Kansas, Colorado, Florida, Nebraska, Iowa, and Arkansas. “Shingle manufacturers will void a warranty on sloped roofs if there’s no room for ventilation; it’s paramount to choose insulation and ventilation products that will encourage and allow the proper ventilation needed.”
Traditional approaches often require additional framing or soffit spaces that can reduce ceiling height and compromise the architectural intent. The church's design also included curved barrel ceiling sections and other complex roof geometries that would make it difficult to achieve consistent thermal performance using conventional insulation methods.
In addition, the roofing assembly needed to satisfy modern energy code requirements, maintain manufacturer warranty requirements for the roofing system, and help protect the decorative interior finishes planned for the sanctuary, like the hand-painted plaster interior ceiling.
"Continuous insulation all the way across is required," said Hare. "It's one of the only ways you can really do that and build to today's code while meeting fire-rating requirements and the shingle manufacturer's warranty."
The Installation
JR & Co. was selected by the general contractor to install the roofing system on the new church structure, and they chose to work with Atlas Roofing Corporation.
"One of the reasons we continue to work with Atlas is that they've consistently proven themselves as a trusted and engaged partner," said Hare. "We've used their products on many projects over the years, so when it came time to find a solution for St. Paul Catholic Church, Atlas was a natural choice. Their team understands how to adapt to the realities of a project, respond quickly when questions come up, and stay involved through every phase of the work. That kind of support makes a difference, especially on a project with as many unique details as this one."
JR & Co. selected ACFoam® CrossVent® and ACFoam® Nail Base products from Atlas, each chosen to serve a specific role within the building's complex roof design. ACFoam CrossVent nailable cross ventilated roof insulation is a thermally efficient above-deck cross-ventilated nailable roof insulation that offers various composite configurations and delivers long-term thermal resistance values. ACFoam Nail Base is a non-structural nailable roof insulation panel comprised of a thermally efficient closed cell polyiso insulation board that provides long-term thermal resistance.
Approximately 500 square feet of ACFoam Nail Base insulation was installed on the church's two front towers and standing-seam metal roof sections. The majority of the remaining roof area utilized ACFoam CrossVent, providing a ventilated insulation assembly beneath the shingle roof system.
The assembly included a base layer of polyiso insulation beneath the ACFoam CrossVent panels. According to the project team, the roof system consisted of a steel deck, gypsum cover board for fire resistance, vapor retarder, insulation, vented nail base assembly, underlayment, and finished roofing materials. The ACFoam CrossVent system was particularly valuable because it allowed ventilation beneath the roof assembly while preserving the cathedral ceiling design. According to Jim Stoddard, district sales manager with Atlas, many roofing manufacturers require adequate ventilation for steep-slope roof systems, and the ACFoam CrossVent assembly helps provide that airflow pathway.
"Cathedral ceilings create beautiful spaces, but they can also create challenges when it comes to ventilation and thermal performance," said Stoddard. "ACFoam CrossVent and ACFoam Nail Base were designed to solve exactly those kinds of challenges. By combining ventilation and continuous insulation in a single roof assembly, the systems allowed the team to preserve the church's architectural vision while delivering the performance required of a modern building."
The project also required careful attention to installation details due to the building's steep roof slopes.
"The majority of commercial roofing is flat," said Hare. "When you add pitch to the roof, getting material up and down becomes more of a challenge, and edge condition details become more critical."
Because the church members intend the building to serve as a permanent home for generations, architectural details received special scrutiny. Custom edge profiles, gutters, and roof transitions were all designed to replicate traditional church architecture, requiring precise coordination between the roofing assembly and the finished appearance.
The Result
The new St. Paul Catholic Church successfully combines historic architectural character with modern building performance.
Choosing the right ventilation and insulation systems enabled the project team to create the dramatic cathedral ceilings envisioned by the designers while delivering continuous insulation, ventilation, and code-compliant thermal performance. The roofing assembly also helps support the long-term durability of the building by promoting airflow and moisture management within the roof system.
For the congregation, the result will be a new sanctuary that reflects centuries-old church architecture while incorporating modern construction practices and energy-efficient building technologies.
For the construction team, the project demonstrates how advanced insulation and ventilation systems can help solve the unique challenges presented by specialty structures such as churches, where aesthetics, performance, and longevity must work together.
As St. Paul Catholic Church prepares to welcome parishioners into its new home, the roofing system above serves as a reminder that achieving traditional architectural beauty often depends on innovative building solutions hidden from view.