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10 <br /> Chapel Hill Old Town Hall Structural Assessment <br /> Page 4 <br /> Load capacity review <br /> Since the capacity of the floor may affect the potential occupancy or use of the building, we also <br /> reviewed the construction documents for the building to determine the uniform live loads that the <br /> floor framing can adequately support. From our review, we conclude the following: <br /> 1. The rear and the southeast portions of the first floor that were built as part of the 1989 <br /> renovations can safely support 100 PSF live load. This confirms the design live load <br /> indicated on sheet S-2 of the 1989 structural drawings. The original framing in the <br /> southwest portion of the first floor can safely support a live load of 50 PSF. <br /> 2. The second floor framing, which consists of original framing except for the area adjacent <br /> to the elevator that was added in 1989, can safely support a live load of 45 PSF at the <br /> area to the rear of the building and a live load of 50 PSF at the southwest and southeast <br /> areas. <br /> The attached reduced plans (Figures 1 and 2) from the 1989 structural drawings provide the <br /> above information graphically. <br /> Based on the current North Carolina State Building Code, the area with live load capacity of 45 <br /> PSF would be limited to uses such hotel and multifamily private rooms and school classrooms. <br /> The areas with at least 50 PSF live load capacity would be limited to the uses such as offices <br /> and the uses stated above. <br /> We have based the live load capacities on a total dead load of 35 PSF, which includes 25 PSF <br /> for the concrete slab and 10 PSF for ceilings, mechanical, electrical, plumbing, and partitions. <br /> To keep the weight of the partitions within the 10 PSF dead load will greatly limit flexibility in <br /> planning the current space and in any potential modifications to the space. Due to this fact and <br /> that the anticipated use of the building would likely require a higher live load, at your request, we <br /> have explored options that would increase the design live load capacity of the floors. <br /> It is our opinion that the most cost effective and feasible way to increase the capacity of the <br /> floors is to remove portions of the existing floor framing and replace it with new structure that <br /> has the required capacity. This would be similar to what was done on the first floor as part of the <br /> 1989 renovations. We recommend that the design live load for the new framing be 100 PSF, <br /> allowing for maximum flexibility in planning the space. <br /> Recommendations for new framing and cost estimate: <br /> The new framing will consist of open web steel joists spaced at 2 feet on center, with 2 inch <br /> concrete slab on 26 gage metal form deck, reinforced with 6x6 W2.1 xW2.1 Welded Wire Fabric. <br /> It is our understanding from the architect that, to provide accessibility at the front entrance, a <br /> ramp may be required at the southwest corner of the first floor. The new framing could <br /> incorporate this ramp by adding at least one new column and footing to support the beam just to <br /> the west of the front entrance so that the end can be removed, allowing the framing to be <br /> lowered for the ramp. <br /> The attached plans (Figures 3 and 4) show the new framing and the approximate location of the <br /> new column. <br /> For planning purposes, we estimate the construction cost to remove the existing framing and <br /> replace it to be between $110 and $150 per square for the areas replaced. The amounts are <br /> LHC <br />