WISCONSIN STATE CAPITOL DOME MOISTURE STUDY
Department of Administration
Project No. 03K3Q
Provide professional architectural and engineering services to perform a close
inspection of the dome of the Wisconsin State Capitol. The purpose of the
inspection is to identify conditions at joints between granite units that may be
allowing water to enter the dome and to identify any other possible causes for the
moisture related problems observed.
In 2000 repairs were made to the dome that included pointing and sealing of
joints between granite units and granite repairs. Since then we have observed
paint degradation around the perimeter of the dome, consistent with high
moisture in the plaster, on the interior plaster finishes at the 10th level, at the
base of the dome. The deterioration is not symmetrical or uniform in pattern and
is generally above the windows and 90% of it is below the interior gutter. There
is additional recent moisture damage just below the interior coffer dome area at
the 8th level. We also observed corrosion on the steel trusses that was not
observed previously.
Water penetration through deteriorated or open exterior joints between granite
units of the dome may be causing the moisture related problems. Inspection of
the exterior of the dome is being done to determine if it is possible that water is
entering through the granite dome’s joints.
We suspect that the dome area and the pipe gallery areas suffer from entirely
different problems. The investigation of the moisture at the 8th level should
probably focus on the exterior deck above the pipe gallery.
DESCRIPTION OF THE DOME
The dome of the Capitol extends from 175 feet above the ground floor elevation
to 236 feet above the ground floor elevation and consists of 24 radial segments
and 14 courses of granite between the skirt course located below the lantern and
the scroll course at the base of the dome. The granite of the dome is supported
on the top chords of 24 steel trusses and at the base of the dome the granite
between the trusses is supported on a brick masonry wall.
Granite infill units that are widest at the base of the dome and taper toward the
top of the dome are set between projecting granite rib units. 24 ribs are made up
of granite units 1 foot 8 inches thick and are located directly over each built-up
steel truss. The granite infill units between the ribs are 8 inches thick and are
connected to the adjacent steel truss at alternating horizontal joints. The units
are connected to trusses by a bent rod attached to a continuous horizontal angle
that spans between the trusses and is connected directly to the trusses. All
horizontal joints are keyed together by a one inch lap cut into the ends of the
units. The top surface of each panel between the ribs is cut to create a reveal
that slopes down from the inner edge. The space between the trusses and
directly behind the granite units is infilled with clay tile. The original drawings
show a 2 inch air space between the inside face of the granite and the outside
face of the clay tile.
The top of the dome consists of a granite skirt course, starting at 231 feet above
the ground floor elevation, a balustrade, starting at 235 feet above the ground
floor elevation, and a lantern, starting at 235 feet above the ground floor
elevation. These elements are supported by the 24 steel trusses. On top of the
lantern stands the three ton Daniel Chester French gilded bronze statue,
Wisconsin.
At the base of each granite rib of the dome, 183 feet above the ground floor,
there is a decorative carved granite scroll with masonry backup. Masonrybacked granite spandrel units are set between the scrolls.
At the top the steel trusses are connected to a steel compression ring that is 10
feet in diameter. At the bottom each steel truss is connected to a steel column
that is connected to a steel tension ring that is 80 feet in diameter. Original
building documents, Drawing 518-2017, dated 28 June 1910, and Drawing 5182016, dated 29 June 1910, show the connection of the trusses to the column and
the connection of the column to the tension ring. The bottom chord of each steel
truss, back-to-back, 5 x 3 ½ x 7/16 angles separated by a 3/8 inch plate, is
connected to a steel columns by a 4 ½ inch diameter steel pin inserted through a
3/8 inch thick steel plate that is riveted to the web of the column. The tension
ring, a built-up steel girder consisting of two 5 x 3 ½ x 3/8 inch angles riveted to a
3/8 inch thick web plate, is riveted to the inner flange of each column.
SCOPE OF WORK
Be responsible for project administration, coordination of contract, billings,
budget, and schedule for the Project.
Review original documents related to the construction of the drum and dome.
Review Wiss, Janney, Elstner Associates, Inc.’s study of the dome and west
wing.
Review documents related to repairs to the dome, including, but not limited to,
recaulking in 1996, repairs made in 1997, and repair and conservation of
exterior granite project in 2000.
Review maintenance records to obtain information on the performance of the
dome and adjacent interior construction.
Interview building management staff and various contractors.
Meet with building maintenance personnel to discuss the ongoing maintenance
issues with the dome and adjacent construction.
Create field inspection data sheets of the dome from existing documents to
document conditions observed.
Closely inspect the exterior of the dome from a boatswain’s chair using industrial
rope access techniques. The inspection shall extend from the base of the
lantern down to the base of the dome scrolls. It will include granite units and
joints as well as roofing, sheet metal and flashing. The inspection will be
done by trained engineers using appropriate equipment for inspection of the
dome employing industrial rope access techniques. The extent of the
inspection shall be limited to visual inspection and sounding as necessary,
detailed field notes, plus photographic and video recording.
Document conditions observed relative to distress and deterioration of granite
units, mortar and sealant in joints, roofing, sheet metal, and flashing materials
on inspection data sheets and record the conditions with photographs and by
video. Each video will be reviewed thoroughly by professional architectural
and engineering staff during inspection so any re-inspections can be
completed as necessary. DSF staff intends to review video tapes during the
inspection.
Document other visible distress conditions observed on the inspection data
sheets and record the conditions with photographs and by video.
Meet and discuss results of all observations with building management.
Prepare a report presenting the results of the inspection and conditions
observed.
Recommend immediate remedial repairs if appropriate.
Recommend repairs and long term maintenance procedures.
Work with Capitol staff to plan the work, include them on an ongoing basis with
respect to all observations. Schedule regular team meetings that will include
Capitol staff.
STAFF
Identify staff and subconsultants to be used to execute the work. Use only highly
qualified personnel, experienced in the work they are assigned and who have
experience working on significant historic buildings. If we do not know individuals
proposed to do the work we may request resumes. We reserve the right to
approve all personnel who are to work on the Capitol.
FEE AND SCHEDULE
After a Consultant is selected, the A/E shall submit a fee on a time and material,
not to exceed basis, clearly breaking down the work as described above and as
required to thoroughly inspect the dome. Breakdown show hours associated with
each task, the hourly rate associated with those hours and include all personnel
and subconsultants. Submitted fee shall include all labor, materials, and
equipment, (including rope access), and all expenses for food, travel, lodging,
printing, reviewing of submittal documents, research, logs, correspondence,
scaffolding, material testing, data loggers, interior and exterior access, and any
other expenses required to complete the work. Submitted fee shall not include
any fees or expenses to make repairs that may be recommended based on
observations.
With the fee proposal, the A/E shall submit a schedule identifying earliest start
date and an estimated duration for the work in number of calendar days.
Recognize weather delays based on average weather conditions for Madison.
AGENCY CONTACT
Dan Stephans, dan.stephans@doa.state.wi.us, 608.266-1417