Facelift Complete: Great Dome is Better than Ever

The Great Dome had been under renovation for quite some time and covered with scaffolding and a tarpaulin tent. Hackers finally just worked them into their creations. But the construction has ended and the finished product, which includes a restoration of the Barker Library reading room rotunda underneath, has been revealed.

Some photos are below, but check out the MIT News Office article by Larry Hardesty for a great slide show and a full rundown of the enhancements, which also included lifting the dome's limestone cladding and injecting a waterproof membrane beneath it.

Then & Now

Restoration Highlights

Research for the renovation began in 2007.

The 75-foot rotunda (diameter and height) now sports its original colors—seven shades of off-white and a patina green—thanks to work done by a paint-restoration company to determine just what these were.

As of Feb. 27 (and for the first time in its 97-year history) the reading room will be open to members of the MIT community any time, any day. There is seating for 55 people.

The dome of the reading-room rotunda is nested inside the 100-foot-wide Great Dome; the two domes converge at the room's circular skylight, or oculus, which is 27 feet in diameter and set in the center of both.

In 1942, the oculus was covered over as a wartime measure. In the early 1950s, it was reopened but blocked by a "luminous ceiling," a plastic disc suspended some 20 feet above the floor. The oculus was later sealed again.

According to the MIT News Office, "The glazing in the Great Dome actually consists of 1,042 blocks of glass, each 6.25 inches to a side and 1.25 inches thick. The blocks are grouped into six-by-six squares; within each square, the blocks are spaced 2.5 inches from each other. The borders between the six-by-six squares are thicker still, so that in fact, much of the 27-foot-wide opening in the dome is occluded by structural supports."