Santa Maria del FioreSanta Maria del Fiore

LanternLantern

Construction TimelineConstruction Timeline

• 1331- Wool Guild assumes responsibility for works in 1331- Wool Guild assumes responsibility for works in CathedralsCathedrals

• 1357- Guild passes Resolution to build nave and aisle1357- Guild passes Resolution to build nave and aisle• 1367- Board of experts prepares plan for church and 1367- Board of experts prepares plan for church and

octagonal domeoctagonal dome• 1368- Resolution sanctioned for this model1368- Resolution sanctioned for this model• 1417- Opera begins to finance studies, plans, and 1417- Opera begins to finance studies, plans, and

models for the domemodels for the dome• 1418- Dome design competition announced; no 1418- Dome design competition announced; no

winner declaredwinner declared• 1420- Second competition for single model, 1420- Second competition for single model,

according to wishes of Officials of Cupolaaccording to wishes of Officials of Cupola• 1420-1436- Construction of Dome1420-1436- Construction of Dome

Construction StatisticsConstruction Statistics

• Total weight raised ~29,000 tons; avg. Total weight raised ~29,000 tons; avg. of over 2,000 tons/year and 8 tons/day. of over 2,000 tons/year and 8 tons/day.

• 2 million working hours (270 working 2 million working hours (270 working days/year) required to complete dome.days/year) required to complete dome.

• Cupola grew an average of 2.5 Cupola grew an average of 2.5 meters/year. meters/year.

• Several million bricks were laid, on Several million bricks were laid, on average 400,00 a year. Only a few average 400,00 a year. Only a few bricks could be laid per man-hour. bricks could be laid per man-hour.

Materials

Timber – tall white fir from the forests of CasentinoSandstone – from quarry of Trassina-ia.Bricks – from kiln in Via GhibellinaWhite marble – from quarries of Carrara and CampigliaMetal – mostly iron (for chains, bars, nails, brackets, templates for specific marble parts, etc.)Rope – from PisaMortar – prepared from quicklime mixed with sand (or possibly, lime mixed with brickdust)

Dome Construction TechniquesDome Construction Techniques

• Double-masonry dome, with a thick inner octagonal Double-masonry dome, with a thick inner octagonal shell connected to a thinner outer shell with shell connected to a thinner outer shell with meridional arched ribsmeridional arched ribs

• 6 horizontal sandstone rings, reinforced by iron 6 horizontal sandstone rings, reinforced by iron chains, resist tensile outward forcechains, resist tensile outward force

• Inner dome is so thick that a fairly thick circular ring Inner dome is so thick that a fairly thick circular ring can be drawn entirely inside itcan be drawn entirely inside it

• Pointed dome (pointed fifth) has half the tendency to Pointed dome (pointed fifth) has half the tendency to burst as a shallower, spherical domeburst as a shallower, spherical dome

• Herringbone brick pattern used to stablize each ring Herringbone brick pattern used to stablize each ring at every level of constructionat every level of construction

• Supporting drum (14 ft. thick) is octagonal in shape Supporting drum (14 ft. thick) is octagonal in shape and surrounded on three sides by octagonal half and surrounded on three sides by octagonal half domesdomes

St. Peter’s BasilicaSt. Peter’s Basilica

““By 1506, St. Peter's Basilica, the main church at By 1506, St. Peter's Basilica, the main church at the Vatican, was too small and decrepit to the Vatican, was too small and decrepit to impress anyone. Following the examples set by impress anyone. Following the examples set by emperors and sultans, Pope Julius II decided to emperors and sultans, Pope Julius II decided to crown the old church with a dome. He hired crown the old church with a dome. He hired Italian architect Donato Bramante to do the job. Italian architect Donato Bramante to do the job. Bramante's vision for the Basilica was simple: a Bramante's vision for the Basilica was simple: a Greek cross with equal-sized arms around a Greek cross with equal-sized arms around a central dome, a church with the Pantheon central dome, a church with the Pantheon perched on top. But Bramante and the Pope died perched on top. But Bramante and the Pope died before much could be built. In 1546, a young before much could be built. In 1546, a young artist from Florence named Michelangelo gained artist from Florence named Michelangelo gained total control of the construction of St. Peter's, total control of the construction of St. Peter's, the largest church in Christendom.”the largest church in Christendom.”

StatisticsStatistics Location: Location: Vatican City, ItalyVatican City, Italy Completion Date: Completion Date: 16261626 Dome Diameter: Dome Diameter: 138 feet138 feet Dome Type: Dome Type: RibbedRibbed Height:Height: 452 feet above the street, 390 452 feet above the street, 390

feet above the floorfeet above the floor Purpose: Purpose: Religious Religious Materials: Materials: Concrete, brick (masonry)Concrete, brick (masonry) Architects: Architects: Donato Bramante, Donato Bramante,

Michelangelo… Michelangelo…

Important DatesImportant Dates

1506- Pope Julius II hires Bramante to create plans 1506- Pope Julius II hires Bramante to create plans for St. Peter’s Basilica and its domefor St. Peter’s Basilica and its dome

1514- Bramante dies, Antonio Sangallo becomes 1514- Bramante dies, Antonio Sangallo becomes capomaestrocapomaestro

1546- Sangallo dies, Pope Paul III orders 1546- Sangallo dies, Pope Paul III orders Michelangelo to take the commissionMichelangelo to take the commission

1564- Michelangelo dies 1564- Michelangelo dies 1586- della Porta’s plan for a new dome is 1586- della Porta’s plan for a new dome is

approved approved 1588-1590- Dome constructed jointly by della Porta 1588-1590- Dome constructed jointly by della Porta

and Fontanaand Fontana 1590-1593- Lantern constructed1590-1593- Lantern constructed

Michelangelo’s Floor Plan(Greek Cross, all arms equal

lengths)

Tension Rings

Internal piers (each ~60 square feet)

Internal Spiral Stairwells (inside piers)

Buttresses for Dome Support

Windows in Drum

Lantern

“It happened that while the cupola (of San Lorenzo in Florence) was being raised Michelangelo was asked by some of his friends: ‘Shouldn’t you make your lantern very different from that of Filippo Brunelleschi?’ ‘Certainly I can make it different,” he replied, ‘but not better.”

-Vasari, Lives of the Artists.

One of the two minor domes, designed by Vignola. Vignola served as second in command after Michelangelo’s death and chief architect from 1565 to 1573.

(Smaller domes are in style of Bramante’s original cupola; thin walled and single layered)

Minor Domes

Deviations in Dome Deviations in Dome Design…Design…

• Michelangelo designed a “true,” Michelangelo designed a “true,” Roman, hemispherical dome (see book)Roman, hemispherical dome (see book)

• Final dome is 20 ft. taller than a Final dome is 20 ft. taller than a hemisphere; the exterior dome is not hemisphere; the exterior dome is not hemispherical and thus not concentric hemispherical and thus not concentric with the inner shellwith the inner shell

• Lantern, which is octagonal, suggests Lantern, which is octagonal, suggests that the dome was to have 8 ribs. In that the dome was to have 8 ribs. In actuality, there are 16 ribs.actuality, there are 16 ribs.

Engraved coin

Additional ReferencesAdditional References

Ackerman, J.S. Ackerman, J.S. MichelangeloMichelangelo. . Zemmer, London, 1961.Zemmer, London, 1961.

Sketches in Casa Buonarroti.Sketches in Casa Buonarroti.