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HomeMy WebLinkAbout08/15/1995, C-3 - AGREEMENT FOR ENGINEERING SERVICES ON THE CITY HALL SEISMIC SAFETY AND HVAC IMPROVEMENTS PROJECT SPECIFICATION NO. 9101-540-552 ���ItI�NI►�IIIIIIIp� Ilulll r MEET I DAT . ulj►lu C t San tuts OBIspo �/ or < COUNCIL AGENDA REPORT rrW "uMAER FROM: Michael D. McCluskey, Public Works Director Prepared by: David Elliott, Administrative Analyss�L SUBJECT: Agreement for Engineering Services on the City Hall Seismic Safety and HVAC Improvements Project Specification No. 9101-540-552 CAO RECOAEWENDATIONS: 1) Award the 'Agreement for Engineering Services on the City Hall Seismic Safety and HVAC Improvements Project - Specification No. 9101-540-552" in the amount of$79,919 to Howard F. Stup & Associates 2) Authorize the Mayor to execute the agreement DISCUSSION: The City Hall Seismic Safety and HVAC Improvements Project has two major components: 1) correcting structural deficiencies to help the building withstand a major earthquake and 2) repairing and improving the heating, ventilating, and air conditioning systems. The attached 1995/97 Financial Plan project request fully describes this project. Howard F. Stup & Associates has already completed field investigations, structural analyses, and schematic design for the seismic safety portion of the project along with life-cycle cost estimates and schematic design for the HVAC portion. These tasks amount to about 30 percent of the required engineering design work. The engineering services specified in the proposed agreement include preparing construction documents and assisting with bid administration and construction administration. The existing steam boiler finally failed in Spring 1995, leaving City Hall without a heating source because the boiler cannot be repaired. Since the entire Seismic Safety/HVAC project will not be completed until Fall 1996, the subcontracted mechanical engineer who worked on the schematic design is preparing construction documents for interim installation of a new hot water boiler in Fall 1995. This new boiler will temporarily provide heat to the lower floor and will eventually be relocated and incorporated into the Seismic Safety/HVAC project. Temporary space beaters will serve the upper floor during this interim period. FISCAL IMPACT: Contract Engineering Cost: Construction Document Preparation (fixed) $79,919 Bid Administration Assistance (estimated) 2,000 Construction Administration Assistance (estimated) 7,000 Contingencies 9.081 $98,000 Budget Available $113,175 The $113,175 budget available derives from existing separate appropriations made for the Seismic Safety Corrections project and the City Hall Boiler Replacement project. These appropriations have been combined. The City Hall Seismic Safety and HVAC Improvements project was approved in the 1995/97 Financial Plan (see page E-12). ATTACEMIENT: 1995/97 Financial Plan Request - Capital Improvement Project For-. of a^reenert is available in Council Office for review. 1995/97 Financial Plan Request CAPITAL IMPROVEMENT PROJECT OPERATION: Buildings and Equipment PROJECT TITLE: City Hall Seismic Safety and HVAC Improvements Description Seismic Safety Improvements: ■ remove the existing tile roof ■ remove and dispose of existing cementitious roof panels ■ strengthen connections between the roof trusses and walls ■ install bracing for interior partitions ■ install a new structural steel roof deck ■ reinstall the tile roof Estimated Construction Cost: $550,000 HVAC Improvements: ■ remove the existing low-presssure steam boiler ■ disconnect existing baseboard steam radiators upstairs ■ strengthen the concrete slab in the rooftop mechanical well to support additional HVAC equipment ■ build a stairwell and install a retractable stair to the rooftop mechanical well ■ replace the existing electrical switchboard to provide adequate power to the new HVAC equipment ■ install a new hot water boiler for space heating ■ install a new air-cooled chiller for air conditioning ■ install two new air handlers for ventilation and air distribution ■ install new ductwork to upstairs areas ■ install 25 variable air volume terminal boxes for precise temperature control ■ install an energy management system which will allow monitoring and operating the HVAC system from a personal computer on the wide area network Estimated Construction Cost: $350,000 Objectives ■ protect the lives of building occupants during a major earthquake ■ preserve the ability to provide essential services following a major earthquake ■ prevent catastrophic failure and emergency replacement of the existing steam boiler ■ improve comfort and productivity for building occupants ■ provide safe access to the rooftop mechanical well Background Seismic Safety Improvements: In 1990 a structural engineering firm surveyed all city buildings to evaluate their ability to survive seismic forces. This firm found that certain structural elements of the City Hall building might not withstand a major earthquake because of four deficiencies: inadequate connections between basement columns and the floor above,insufficient horizontal bracing at the lower chord of the roof trusses, unanchored cementitious roof panels, and unbraced non-bearing masonry interior partitions. The basement column connections were strengthened in 1992. In 1992 another structural engineering analyzed the remaining three deficiencies and recommended a project to remove the existing tile roof, correct the structural deficiencies, and reinstall the file roof. The need for this work became acutely apparent after the 1994 Northridge earthquake. In that quake, damage commonly occurred where unanchored panels bounced out of metal channels and fell into areas below. Exactly this kind of hazard exists at City Hall. The entire sloped area of the roof is formed by unanchored cementitious panels (each measuring four feet by three feet by two inches thick and weighing about 100 pounds) lying in channels formed by the upper C- 3-02 City Hall Seismic Safety and HVAL ..aprovements (continued) chords of the roof trusses. A major earthquake could dislodge these panels and cause them to fall through the attic and into the office areas below. The recommended project would correct this safety hazard and minimirisk to occupants and equipment. It would also help ensure that essential services could continue following a major earthquake. HVAC Improvements: The original, antiquated steam boiler at City Hall is 40 years old and on the verge of irreparable breakdown. Several components appear to be severely corroded and could not be patched or repaired if they failed. Though it was designed to heat only the upper floor through steam radiators, since 1976 it has also heated the lower floor via a heat transfer device which converts steam to hot water and uses the hot water as a heat source for a forced air system. Because many of the wall-hung steam radiators upstairs have been removed or bypassed, heating upstairs is very ineffective. There is little or no thermostatic control for most areas, and the system's ineffectiveness has spawned a proliferation of inefficient and wasteful electric space heaters throughout the building. In 1991,a mechanical engineer confirmed the condition of the steam boiler and recommended replacement in the short term before its failure. Over the last six years, the building maintenance section has kept the system limping along. In January 1995,the boiler failed, but maintenance crews patched ssssit up by circulating through it a chemical which temporarily stopped the leaks. This patchwork repair will not last through another cold season, and the entire HVAC system needs an immediate comprehensive overhaul. Policy Links Adopted building maintenance program goals: productive work environments, safe and energy-efficient buildings Worst Completed Conceptual designs for the seismic safety improvements and the HVAC improvements were completed under separate contracts. At that point, it became obvious that combining the projects would save money. For example, a contractor could accomplish the HVAC work in the attic much more easily after removing the roof for the seismic safety correction work. Schematic design work for both improvements was completed under one contract. This work included schematic architectural, structural, mechanical, and electrical drawings; a cost estimate; a preliminary construction phasing plan;and a life cycle cost analysis of two HVAC designs. Costs To Date 1995-96 1996-97 1997-98 1998-99 Totals Study 40,000 40,000 Design 80,000 80,000 Construction 900,000 900 000 TOTALS 11A,000 900,000 1,020,000 Revenue Sources To Date 1995-96 1996-97 1997-98 1998-99 Totals General Fund 120,000 120,000 Debt Financing 900,000 900,000 TOTALS 1 1209000 1 9009000 1,020,000 C 3- 3 City Hall Seismic Safety and HVAC ..uprovements (continued) Schedule Complete plans and submit for building plancheck 1/96 Complete construction documents 2/96 Advertise for construction contract bids 3/96 Award a construction contract 5/96 Start construction 7/96 Public Art Public art would be difficult to incorporate into this project. There should be a one percent in-lieu contribution to the public art project account based on construction cost. Project Options Forgoing the Entire Proiect. If the HVAC improvements were not completed, the boiler would fail sometime during 1995 or 1996, and there would be no heating system for City Hall. This failure would require emergency installation of at least a new boiler along with heat/vent f mcoils and ductwork for upstairs areas. Under emergency deadlines and without the easy access provided by removal of the roof,this work would be much more expensive. If the HVAC system is not replaced after the boiler fails, the city would have to resort to some arrangement of space heaters, which would be very expensive to operate and relatively uncomfortable to work with. If the seismic safety improvements are not completed, City Hall would remain vulnerable to a major earthquake, which would probably cause extensive structural and equipment damage and pose a moderate risk of injury or death to building occupants. Eliminating Air Conditioning. Eliminating the air conditioning components of the HVAC improvements would reduce construction cost by$100,000 and operating cost by$300 per month, compared to the recommended project. But this option would sacrifice potential comfort and productivity for occupants. The building's masonry walls and site orientation allow uncomfortably wide interior temperature swings, particularly along the Palm and Osos Street frontages. These temperature swings would continue without air conditioning to modulate them. Also, eliminating air conditioning would eliminate the opportunity to use variable air volume terminal boxes for precise temperature control in individual zones. Reeving the Cementitious Panels in Place. It might be theoretically possible to keep the cementitious roof panels in place in order to avoid removing the roof and save construction costs. To reduce seismic hazard, these panels would have to be positively secured to the roof trusses with some kind of mechanical fastener. But attaching mechanical fasteners would require penetrating the panels, which contain non-friable asbestos. This asbestos is harmless if left undisturbed but potentially hazardous if broken or penetrated. Effect on the Operating Budget Operations. Adding air conditioning to the HVAC system would marginally increase net monthly energy costs from existing levels. Most of the additional cost for air conditioning would be balanced by savings from heating efficiency, where central heating would replace inefficient electric space heaters. Debt Service. Beginning in 1996/97, aanual debt service costs would be about $80,000. 6- 3-�/