Serving Congress and the Supreme Court, preserving America's Capitol, and inspiring memorable experiences

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Dome By-The-Numbers

Dome By-The-Numbers

Dome Restoration

1.1 million pounds weight of the scaffold
75,000+ pieces of equipment
52 miles of scaffold pipe
2 miles of decking, enough to build a sidewalk 5 feet wide x 2 miles long from the US Capital to the Lincoln Memorial
1,215 gallons of paint will be used to repaint the Dome - 3 layers x 405 gallons each. Final top coat color is "Dome White."
5 layers of safety netting in Rotunda
14,700 square feet total Rotunda saftey netting square footage = approximately the size of two tennis courts
6,100 lbs. total weight of Rotunda netting

 


Dome Weight

8,909,200 pounds weight of Dome = approximately 4,500 tons = about the same weight of 20 Statues of Liberty  

Dome Exterior Height

376 feet height above Potomac River (includes Hill elevation)
288 feet height above East Front Plaza including Statue of Freedom, is the tallest cast iron dome in world approximate height 29 story building
210 feet height above East Front Plaza to the balcony used for Dome tours at Tholos 
199 feet height of Dome measured from Dome Skirt to Base of Freedom
555 feet height of the Washington Monument is 267 feet taller than the U.S. Capitol. Because the base of the Washington Monument is 30 feet above sea level, and that of the Capitol is 88 feet above sea level, the top of the Washington Monument is 209 feet higher than the top of the Capitol Building.

Dome Diameter

135 feet measured from exterior
96 feet measured from interior 

Rotunda

180 feet from Rotunda floor to top of the Apotheosis; the Statue of Liberty without her base would fit with room to spare (she is 151 ft)
85 feet from Rotunda floor to first visitor gallery
149 feet from the Rotunda floor to the second visitor gallery
20 feet from the bottom edge of the Apotheosis to the apex at the center of the hemisphere  

Windows 

108 in Dome
36 windows in Cuploa
36 windows in second story
36 windows in Peristyle
12 windows in Tholos

Iron

36 hollow cast-iron columns in peristyle set 10 degrees apart around 360-degree circle
12 columns in Tholos
14 over lapping cast-iron plates make up one section Copula
3/8” to 1/2 " range of thickness of cast iron in Dome
5/8 thickness of cast-iron in the Dome Skirt

Decorative Features

288 balusters in Boiler Plate Balustrade
80 lbs. approximate weight of decorative acorns
72 acorns total decorative acorns
36 up-facing acorns  
36 down-facing acorns 
36 grape clusters
4 300 watt “in-session” light bulbs Tholos


Statue of Freedom

Weight

15,000 pounds = approximate weight of 4 cars

Height

38 feet tall Statue of Freedom with base = approximately as high 4 story building
19.5 feet statue height without pedestal
18.5 feet height of pedestal

Base

12 wreaths are on the base of the Statue of Freedom
12 fasces, symbols of legislative authority, are above the wreaths

Headdress

10 lighting rod points sit atop Freedom’s Roman inspired headdress with native American influences