DAVID S. POTTRUCK HEALTH AND FITTNESS CENTER

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1 Project Delivery Evaluation Executive Summary How a project is delivered is very important to successfully completing a project on time, and with in the given budget. For many projects, they can follow a typical delivery system, such as building a Wall Mart or McDonald s. However, with unique construction like the Pottruck Center how a project is delivered can be critical to meeting the owner s goals. By bidding the project as negotiated work with no incentives, and selecting Sordoni to deliver with a system that works well for unique projects, the owner secures the quality of the project, and is able to more easily make changes to small portions of the overall scope. The project team is also experienced enough to visually monitor schedule and cost. Progress of work can be observed, and then schedules can be adjusted for short term analysis. The MEP coordination efforts were not as critical to completion as it is in many other buildings due to the relatively simple scope of work for the technical systems. The use of off site heating and cooling of water, and off site steam production, reduces much of the normal required coordination efforts. The only major areas that needed any coordination were the soffit space above hallways, where the majority of the ductwork travels through the building. The delivery process used for the Pottruck center was well suited for this type of construction. 1

2 Contract Analysis Construction Manager Normally, the University of Pennsylvania will specify a lump sum contract, with the lowest bidder winning the project. The Pottruck Center was designed with enough unique features and constructablity issues that the owner decided that a negotiated contract, using a guaranteed maximum price format, would be better able to deliver a building that would meet their expectations. The construction manager, Sordoni Skanska, would build the project for their bid price plus a fee, and any money saved during construction would be returned to the owner, and possibly re-circulated back into the project. The contract calls for compensation of actual damages if the building is not substantially completed on time. This is unusual in that most contracts will have a liquidated damages clause. Disputes are to be handled by a board of arbitrators pre-selected by the owner and contractor. Design Team The contract held with the owner was a typical design contract, with a design cost plus the architect s fee. The Architect was required to hire the appropriate engineers to design the structural, mechanical, and electrical. The architect held similar contracts with its engineers as the owner held with the architect. As part of the contract, the architect was required to make a consultant available to oversee constructablity issues during construction and provide guidance to the contractor to resolve these issues. Many of the final finish items were finalized as the building was close to being prepared for their installation. Types of contractor contracts There were three different types of contracts used to hire contractors to build the Pottruck Center. First, the typical subcontractor was hired for any major part of the building, mainly any scope of construction over $100,000. The Purchase Order (PO) contract was used to buy specialty items that would be installed by contractor already hired by the Construction Manager. Items like lockers and combination seat/cabinetry units were PO contracts. The third type of contract was an Agreement to Purchase Materials (APM) contract, which was used to bill out specialty items that were low in cost, but required a special contractor to be installed correctly. These items would be built and installed by the PO contractor. The reason for the PO is to simplify the contractor/subcontractor relationship, where the contractor just pays off the subcontractor whatever the cost of that item was, without any close scrutiny of cost. Subcontractors Subcontractors are hired by and communicate direct to the construction manger. Contracts a broken down into the scope of the building that each subcontractor is responsible for. Almost every contract is a lump sum contract with an allowance built in to the contract bid price. If the 2

3 allowance that the contractor holds with the subcontractor is not needed to complete the project, the allowance becomes a return to the construction manger. The terra cotta panel system, because of it s unique design and construction, was assembled as a joint venture design build contract. The designer of the system was Moeding a German engineering firm, while the builder of the panels was Schilden, and the installer was Architectural Facades, Inc. These contracts worked very well in delivering the project. Subcontractors were required to deal directly with the project team. They did not have any direct interaction with the owner. Any disputes are first taken up with the field personnel, or superintendent, and then taken to the rest of the project team if a resolution can t be reached in the field. The owner may be asked to play the role of a decisive opinion if there is a major impasse with the scope or cost of work to be done. The Subcontractor is required to carry five types of insurance. General Liability will cover third party incidents due to construction. This covers pedestrians being injured from debris, equipment, or accidentally walking on site, and then suing the contractor or owner. Automotive insurance is also required to cover any damages to or by the subcontractor or other s nonconstruction vehicles. All subs are required to carry workers compensation insurance for the payment in the case that an employee of that company becomes injured due to construction related activities. There is also Excess Liability that covers overages of any amount of cost above the coverage of any of the other insurance policies. In comparison with other Sordoni Skanska projects, this one follows their traditional project delivery. For the most part, Sordoni does negotiated work, and only delivers projects as a construction manager. This method keeps their overhead costs low, while allowing the project team to be independent of the central office. Each project is self sufficient, with small estimates, schedule and scope changes handled on site, by the construction team. This system is used regardless of the type of work, with only slight variations to the project team set up. 3

4 Contractor Selection All Contractors and Subcontractors were pre-qualified for selection to bid the Pottruck Center. In the past, the University had conflicts with several different contractors, and as these conflicts arose, they created a list of contractors that they would not hire. Qualification surveys were sent out to certain contractors, and based on these surveys, invitations to bid were sent out to the contractors that met the pre-qualified requirements. Each subcontract had three to five bidders, with the low bidder receiving the contract. Occasionally the low bidder had to be thrown out because the bidder did not bid the system correctly, and had a bad estimate. The project team would always breakdown the lowest bid to make sure that the number was a good estimate. The lowest reasonable bidder was always selected, with no preference given to companies that may do a lot of work for the University. The terra cotta panel system only had one available contractor at the time, so there was not a competitive bid for that scope of the building. Contractor Selection was more difficult for the lower cost items that needed to be contracted with purchase orders or APM s. Items like the emergency generator (APM), misc. concrete (PO), and signage (PO), all worked out well as their respective contracts. However, the rooftop air-handling units were billed out as a purchase order, and should have been bills as an APM due to the work involved with installing the plumbing systems within the units. 4

5 Staffing Plan Owner Project Manager Project Exec Superintendent Assistant Project Manager Project Engineer The Project Manager has ultimate control of the project s construction. He is the primary source that the owner will communicate with on almost all matters. The Project Executive oversees some of the overall construction issues, like monthly budget reviews and selecting contractors, but in general does not play a major role in the management team. He only dedicates 3-4 days in a month to the project during the first half of construction, and 12- days a month there after. The Superintendent will answer to the Project Manager, but has the power to resolve most field issues, and to drive the schedule. The Assistant Project Manager takes on mach of the MEP coordination, and deals directly with many of the subcontractor project managers. On this job, the Assistant quit soon after topping off, and the project engineer assumed part of his duties, with the Project Manager taking the rest. The Project Engineer maintains the contract documents, drawings, submittals, and is also responsible for a few subcontractors. 5

6 Design Coordination The major issues with coordinating the installation of the various mechanical, electrical, and plumbing systems were the location of ducts, sprinklers, and the recessed light fixtures. The building makes optimal use of its corridors to contain the bulk of the ductwork through out the building. Branching ductwork was not allowed to travel through the open fitness facilities due to the exposed ceiling, and the interior architecture/design. So running the main branches of the ductwork and sprinklers was to be contained in the limited covered plenum space, mostly in the corridors. The ductwork and sprinklers had frequent conflicts, where the sprinkler system had to be adjusted, as the ductwork had little tolerance to changes. The recessed lighting fixtures also posed an issue, as the specified lights were several inches taller than the space allotted for them between the ceiling and the ducts running above. The MEP coordination task was given to the Assistant Project Manager, and was to be coordinated between the subs, contractor, and all changes major to be approved by the architect. No MEP coordination was specified in the contracts, and there was no use of CAD drawings or overlays, as most of the problems encountered were with height restrictions. The majority of the sprinkler/mechanical conflicts were dealt with in the field as issues came up. There were no real issues with the mechanical room coordination, because water was chilled and heated off site, and the steam for the heating system was made off site as well. There were a few conflicts with the structural system and the MEP systems. Some of the steel had to be ordered with openings in it to accommodate sprinkler branches. Occasionally some pieces of steel had to be adjusted in the field, but this was rare enough to almost be a non-issue to cost of schedule. When any system was significantly altered or moved, the subcontractor recorded as-built conditions. These as-built drawings were a required part of the subcontractors contact to receive final payment. Required testing on the building systems was: concrete, fire protection (water pressure test), structural steel inspections, soils compaction tests, grout and water protection inspections. Most of these tests were performed as the systems were completed, and not left until the end of construction, as failure to pass would have held up substantial completion. 6

7 Project Controls Monitoring of construction was mainly left to the superintendent, who would also drive the schedule of the building. Giving him observation and scheduling allowed for a comprehensive estimate of schedule time to be reached on short-term intervals. Frequent updating of the schedule also allowed the project team to assure the owner that milestone dates were going to be met. Quality of construction was the main responsibility of the subcontractor. The project team would keep close watch on all construction, and bring up questionable work to the field personnel, who would then be responsible to improve the quality to the required standards. Occasionally the subcontractor s project manager had to brought in to discuss the change that was required if it was going to be a major cost issue. Safety issues were handled by the entire project team while walking around the site. The contractor was able to keep a safe site by making frequent checks on the amount of debris laying about the site, and making sure all workers were following safety guidelines. The contractor also employed a general laborer, whose main purpose was to maintain the building and site, and watch for safety hazards. Cost issues were dealt with on a monthly basis, to accompany the 30 day payment period. As each subcontractor would bill for work completed, the superintendent would be consulted to asses the percentage of the work that was completed. The percentage of completed work should roughly match that of the percentage of the contract that has been billed. If the work completed does not seem to match billing, then a detailed breakdown is produced to determine how much the subcontractor would be paid. Milestones are also important to monitoring the project cost. During the last 3 months of the project, when all the finish work was being done, a cash flow diagram was created to project how much payment would be due to each subcontractor. 7

8 System Analysis The Pottruck Center façade features a unique terra cotta panel system that has not been used before in the United States. The façade that will be covered by the terra cotta is not vertical, but angled in towards the building. This angled system would be very difficult to construct in the field. Therefore, a new system was designed where the majority of the work is done off site. Panels twenty feet long are constructed, brought to the site, and fastened into place with minimal effort. The panel consists of there parts, the frame that secures to the structural steel, the insulation and waterproofing inside the panel, and the terra cotta tiles fastened onto the front of the panel. There were two alternatives available tot his system. The first was to pre-assemble the frame and insulation only, then install the terra cotta tiles on site. This option was not feasible, due to the incline that the façade design requires for the terra cotta. This system is better suited for a design that has a more complicated tile pattern, and to avoid the need for expansion or control joints, like are required by the panel system. The second option for the installation was to assemble the frame, insulation, and tiles on site. This is much better suited for a façade that does not have any repetition, which could not be pre-made into panels. Overall the best system to install the panels was chosen for this project. The panels can be installed quickly, and with a learning curve, the same crew can install each panel, and become quicker as they move along the building. Some improvements that could be made to this system is the installation process, or integrating the window frames and sills better into the fabrication of the panel. Integrating the frames would greatly increase the speed at which the windows could be installed, increasing the date of substantial enclosure so that interior finish work can begin sooner. The structural system has very little room for design change. Each floor as the structure rises extrudes further out from the building, so that each floor is required to be cantilevered several feet out from the closest column line. Changing the design to concrete would be too costly to keep the cantilevers, and there really aren t too many different ways to erect steel. One problem that did come up during construction was that many pieces weren t designed of fabricated correctly. However, this was a design team problem that the contractor could have little control over. The Mechanical system is a 50% fresh air system, with three air handling units. Each unit is dedicated to certain area of the building. The main unit services all the fitness spaces, while the other two serve the offices, and the locker rooms. The 50% air change per cycle is not an efficient method, but is specified to increase the comfort level and reduce the recirculation of moisture and odor. One area of the building that was overlooked in the design was the ventilation of the four story atrium. This space is only serviced by a few air supply registers in the soffits at the ground level. This lack of conditioning was a cost saving measure of the design 8

9 that makes sense for initial and long term cost savings. However, this space has the potential to cause major discomfort because of the skylight roof of the atrium. The Atrium has a fire safety system at the top in the form of smoke exhaust vents. These vents have sensors that detect smoke, and turn on to prevent accumulation of smoke in the atrium in the event of fire. To help alleviate the accumulation of stuffy, uncirculated air at the top of the atrium, the smoke vents could be run once an hour or so, just to vent the hot accumulated air from the summer months and at larger intervals during the winter to remove the air that isn t circulating any other way. The problem with this system is that the smoke exhaust fans were not meant to be run consistently. Specifying some different equipment may be necessary to use the system on a daily basis. 9

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