Jubilee ChurchTor Tre Teste, Rome, Italy

Richard Meier1996 - 2003

Dukyoung Lee

General Information

• The Jubilee Church, formerly known as Church Dio Padre Misericordioso, sits on a flat, triangular site. The building features concrete, stucco, travertine and glass. Three dramatic concrete shells arc in graduated heights ranging from 56 to 88 feet that elicits gliding white sails. Glass ceilings and skylights span the entire length of the building filling the space with natural light. At night, light radiates from within creating an ethereal presence. As Meier describes it:

“… Light is a means by which we are able to experience what we call sacred… In the Jubilee Church, the three concrete shells define an enveloping atmosphere in which the light from the skylights above creates a luminous spatial experience, and the rays of sunlight serve as a mystical metaphor of the presence of god…”1

The Main Structure

• The Jubilee Church’s 9,000-square-foot massing is defined by three concrete shells, ranging from 56 to 88 feet in height. The shells, which are segments of a sphere, demarcate three distinct spaces -- the main sanctuary, the weekday chapel, and the baptistery, each with its own entrance. Separated by vertical expanses of glass and skylights that span throughout the entire building, the shells in appearance seem to be freestanding and to be reaching over towards the “spine” wall, but in reality, they are cantilevered onto the ground.

Structural Plan of the Jubilee Church

The Curved Walls and the Cantilever Effect

• The three large white shells on the south perimeter of the church curve up and over the main body or the “spine” of the church and are partial concentric spheres that are seemingly filled with an easterly wind.

• Meier remarks, “Each shell is literally free standing and cantilevered from the ground.” The shells are tied down to the ground to resist seismic wind loads. Thus, the shells act as vertical cantilevers, and the ground as the fixed end accordingly.”2

• As mentioned above, wind load resistance is developed through a vertical cantilever effect, acting across the full depth of the cross section. These walls are composed of inner and outer shells that are connected by a diaphragm.

The loading of a concrete panel

The Concrete Clad Shells

• To cope with the height of the sails -- the tallest of which is 88 feet or 26 meters high -- and their double curvature, Richard Meier turned to Italcementi, one of the largest producers and distributors of cement in Europe.

• For the construction of the shells,which are spherical, curing horizontally as well as vertically, 256 double-curved, prefabricated elements were utilized. The joint between one block and another, which is considered the most distinctive and unique feature of the entire structure, was designed and carried out to allow connection between the pre-tensioning bars and to ensure stable continuity to the structure.

• Each pre-cast block had to be lifted and set in place adjacent to others with the greatest accuracy according to the sail’s geometry to permit interconnection of the bars. The pre-cast concrete segments were then post-tensioned in situ.

Pre-cast blocks with pre-tensioning bars

The Steel Bars

• According to John Eisler, project manager of construction of Jubilee Church,

“Think of a globe turned 90 degrees. The parallels run vertically [in this scenario], and the meridians run horizontally. As a result, a single stainless-steel form, adjustable on the ends only, can be used for every block.”3

• Both pre-tensioning bars and post-tensioned steel was used as reinforcement for the concrete-clad shells.

• Meier placed a narrow slot at floor level on on of the shells to emphasize the non-load-bearing aspect of the concrete panels immediately above it, versus the steel skeleton frame hidden within the shell.

Steel bars in between the pre-cast concrete panels

The Narrow Slot at floor level

The Joints

• Going along with the construction system of the post-tensioned pre-cast concrete clad shells, Meier decided not only to expose the concrete, but also to articulate the joints. According to Meier, “We wanted to express each panel, yet minimize the joints and keep them tight for weatherproofing and for the expression of the shells.”4

• The joining pattern combines two distinct geometries: Horizontal radial lines from the three concentric spheres intersect the parallel vertical lines derived from minor spheres.

• Joints at skylights, glass ceilings and window walls accommodate the independent movement of the stiff shells, which are mainly due to temperature effects on their southern exposures and also by wind and seismic loads. An arched steel truss, held back with a series of horizontal rods, supports the center of the glass roof over the main nave.

Structural Plan of the Jubilee Church

Detail at skylight and wall over nave

The Construction Process

• As mentioned before, the pre-cast concrete blocks had to be maneuvered with extreme precision within a limited area of action. Italcementi, or rather Gennaro Guala in particular, came up with a solution, by developing a special, 32-m high curving gantry crane. This machine allowed each precast block to move toward the exact X-Y-Z axes.

• Interesting Fact: Italcementi actually developed and patented a new type of cement -- Bianco TX Millenium -- in response to Meier’s requested aesthetic quaality. Other than having great strength and more efficient workability, Bianco TX Millenium provides an extra quality: when exposed to light, the photocalyst particles in the cement stimulate a self-cleaning process on the surface so that the brightness and color will not degrade over time.

The curving gantry crane

The Construction Process

Close-up of the Openings of the first and second shells

The Construction Process

The curving gantry crane and the three shells before the pouring of concrete

The Construction Process

The three shells after the pouring of concrete and post-tensioning

The Construction Process

The three concrete-clad shells and glass curtain walls

Sources

• 1Via F. Tovaglieri, Church Dio Padre Misericordioso, Rome, 1998-2006, http://www.galinsky.com/buildings/jubilee/index.htm (May, 2006)

• 2Paul Bennett, “When in Rome”, Architecture (December, 2003): 94-101

• 3Sara Hart, “Dynamic Concrete in the 21st Century”, Architectural Record (October, 2001): 180

• 4Paul Bennett , “When in Rome”, Architecture (December, 2003): 94-101