The Edna Maguire school was initially designed to accommodate solar panels with a weight allocation of approximately 3 lbs per square foot placed upon the roof. This was designed under the governance of the 2010 California Building Code. All California Public Schools are State property and therefore come under the jurisdiction of the Division of the State Architect (DSA) and not local building departments. Hence, any modifications would be subject to DSA reviews and approvals. The approximate design loads for structures include the two (2) basic load components of 1) live loads which are transient and include people, toolboxes, leaves, re-roofing equipment, debris, snow (not applicable at Edna) and other items that are not fixed as part of the building structure, and 2) dead loads which are composed of the elements that are fixed and make up the building structure and other fixed components such as lights, ceilings, roofing, etc. The original building design assumed accommodating future solar at 3 lbs per square foot into the dead load since solar panels were assumed to be eventually ‘fixed’ to the building. The live load allocation to the roof was approximately 20 lbs per square foot. In the case of Edna Maguire, live load and dead load are close to equal.  Dead load is important as there is a part of the current building code (CBC Chapter 34) that allows for a post-construction increase in dead load of 5% of the dead load allocation. So, in essence, there is latitude to increase the fixed or dead load by approximately 1 lb per square foot assuming approximately 20 lbs per square foot of dead load. The governing codes traditionally are updated every 3 years and therefore are continually subject to changing these allowances.

 

 

During the bidding of Edna Maguire there were dramatic construction price increases occurring throughout the Bay Area. As a result, the bids for Edna came in approximately $5 million over the target price. In response to high bid results, the District and construction managers initiated ‘value engineering’ (VE) exercises to reduce cost from many elements of the building design. This VE exercise included modifying the design of the ceilings from an architecturally appropriate exposed “acoustical steel deck” to basic (non-aesthetic) structural steel deck with the inclusion of the suspended acoustical grid ceiling that you now see throughout the Edna interiors. This design change resulted in approximately 2-1/2 to 3 lbs of additional weight for the ’suspended ceiling' that was not foreseen in the original design. The post-design inclusion of the suspended acoustical ceilings depleted the 3 lbs of allocation for future solar panels for Edna’s roofs.