Sweeping down a hillside in Tegucigalpa, Honduras, a curved metal roof encloses the Templo Ministerio Cristiano de Restauración Familiar. The curved roof hugs the sloped site. Additionally, inside the building, the underside of the roof is exposed, allowing occupants to experience the curved shape of the roof and structural details.
A curved metal roof and custom building structure provide ample interior space
Photo: Claudio J. Alcerro Tejeiro
Judges for the 2023 Metal Architecture Design Awards commended the ambitiousness of the project. They lauded it for being a daring solution that did a lot with a little in terms of a relatively minimal budget. The judges noted the project addressed the site’s topography with the form of the building and its position on the site. For these reasons and more, they recognized the Templo Ministerio Cristiano de Restauración Familiar with a Design Award in the Metal Roofing category.
Sloped Site, Open Space
Regarding designing the building to respond to the contour of its hillside site, Dino Rietti, architect at Tegucigalpa-based Arquitecnic SRL, says one primary driver of the design was to create as much interior space as possible on the hillside site.
“The main goal was to build a temple without the need for internal support columns or walls to create a unique and modern place of worship with a large, open space,” Rietti says. “The answer was an amphitheater concept in a diamond shape supported by 24 columns, with 12 doors in between the columns. The building is georeferenced to the vertical and horizontal axes. The topography is irregular and sloping, so the building is embedded in the hill in a tridimensional point disposition. The main arch rises more than 35 feet from the lower-level support to the higher-level support and spans 215 feet.
“We developed an authentic structure for the temple composed of a long span arch as central support and four perimetrical arches in each façade to obtain a clean, open space. The floor is formed by curved steps that are embedded in the hill and adapted to the natural terrain.”
Photo: Claudio J. Alcerro Tejeiro
Shell-shaped Roof
More specifically about the roof design, Rietti says, “The shell shape looks curved, but is sectionized in small vectors, or voussoirs. The symmetry of the roof separates the area in two parts by the center arch. Each area is bent like a hyperbolic paraboloid produced by each long span joist supported in the perimetrical arches in one side to the central joist in the other side. Then, the secondary structure, the smallest joist, attaches the sheet metal to form the shape of the roof. The sheet metal roof was bent precisely, and was manufactured on-site to perform each longitudinal size and shape.”
Custom Roof Construction
For the roof, Proyectos Metalicos Alcerro SRL (PROMETAL Honduras) in Tegucigalpa rollformed 24-gauge Galvalume coil in White into a double-lock standing seam roof system. The metal coil was distributed by Amanco/Wavin in Tegucigalpa, Francisco Morazán. The panels are 11 inches wide and have 2-inch-tall seams. Some panels are longer than 95 feet. To prevent leakage, the panels do not have cross-joints.
Claudio Alcerro Tejeiro, project manager at PROMETAL Honduras, says, “Customized clips were built to anchor the double-lock standing seam sheets. We used chemicals and special rivets to prevent noises and squeaks produced by temperature changes and contact between metal surfaces, considering that all rivets wouldn’t be exposed or visible at the end.”
PROMETAL Honduras also fabricated and installed 24-gauge Galvalume lateral rainwater gutters in White.
Photo: Claudio J. Alcerro Tejeiro
To build the roof structure, PROMETAL Honduras fabricated and installed steel plates and steel square tubes. Several gauges of steel plates were used including 2-inch-thick plates. Also, several gauges of steel square tubes were used including 3/16- and 1/4-inch-thick.
The centerline of the roof, above the main arch, features a translucent panel system. PROMETAL Honduras fabricated and installed Allentown, Pa.’s Palram Americas Inc.’s SUNLITE brand 0.314-inch-thick, 6.89-foot-wide by 19.02-foot-long, polycarbonate panels in Opal.
Intricate Building Structure
With respect to building the building structure, PROMETAL Honduras completed a structural analysis.
“We proceeded to develop the design and structural analysis starting from the foundations, anchors, primary and secondary structures, and roofing system,” Alcerro Tejeiro says.
PROMETAL Honduras fabricated steel anchors customized with holes to fill them with concrete. The steel building structure includes the main, central arch with structure reinforcement plates, 12-inch-diameter columns, lateral arches, joists, support and bearing plates, and square-shaped tubes.
“To maintain precision since metal structures deform when subjected to high temperatures due to welding, we constantly supervised engineering, always minimizing the errors between the blueprints and field measurements, using precision tools that provide accurate information,” Alcerro Tejeiro says.
Photo: Claudio J. Alcerro Tejeiro