COUNTY OF SAN MATEO

Inter-Departmental Correspondence

Department of Public Works

DATE:

March 13, 2002

BOARD MEETING DATE:

March 26, 2002

TO:

Honorable Board of Supervisors

FROM:

Neil R. Cullen, Director of Public Works

SUBJECT:

Waterproofing of the Cupola of the San Mateo County Courthouse - Redwood City Area (Project No. P6801)

Recommendation

Adopt a resolution adopting Plans and Specifications, determining prevailing wage scales and calling for sealed proposals to waterproof the Cupola of the San Mateo County Courthouse (Old Courthouse).

Previous Board Action

Authorized a lease of the Old Courthouse to the San Mateo History Museum (Museum).

Key Facts

1.

The lease with the Museum provides that the County is responsible for the exterior of the Old Courthouse.

2.

The cupola (dome) of the Old Courthouse is not water tight because the seams and joints between the copper and glazing on the dome have failed.

Discussion

The dome assembly of the Old Courthouse was built in 1904 and withstood the 1906 earthquake which destroyed most of the main building. The Courthouse was reconstructed in 1910 and the dome was integrated into a new courthouse structure. The dome is comprised of a wood and steel frame overlain with copper. The dome also supports the copper framing that holds the individual pieces of glass of the dome. The dome's ability to resist leaking is based on the original design of the copper seams and joints and how they hold the individual pieces of glass.

The original folded and soldered seams have been subjected to thermal expansion and contraction over many years, which has fatigued the solder and caused cracks to develop. This has resulted in leaks in the dome. There have been attempts to use an elastomeric sealant without removing the glass pieces, but this has not been successful as a good bond between the sealant and the existing copper and glass could not be attained. The copper has naturally oxidized over time and the sealant does not readily and consistently adhere to this material.

The proposed project requires that the copper glass framing of the dome to be carefully cleaned, and in some cases disassembled, reassembled and sealant reapplied. Although this work is labor intensive, we believe it is necessary to make the dome watertight.

We have also included bid alternates to:

·

Repair the courtroom skylight in the Old Courthouse; and

·

Repair or replace ornamental copper on the dome

This work can be included depending on the bids that we receive for the work, and we will report the cost of the work if your Board approves this project and after bids are received.

Vision Alignment

We believe our recommendation is consistent with Goal Number 20, "Government Decisions are Based on Careful Consideration of Future Impact, Rather than Temporary Relief or Immediate Gain," of the Shared Vision Commitment to provide a "Responsive, Effective and Collaborative Government," as the Old Courthouse is part of the heritage of the County and this project will help to preserve this facility for the enjoyment and education of future generations.

Fiscal Impact

The project is estimated to cost $372,500 not including proposed alternate bids. An appropriation of $453,000 for the work was approved in the 2001/02 Capital Projects Budget and is financed with $125,000 in State grants, $53,000 in Court House Construction Funds and $275,000 in General Funds.

A form of resolution has been approved by County Counsel.