A construction company is investigating two forming options for a new hotel project. Option A is the use of large-panel forms for the walls and table forms for the slabs. Option B is tunnel forms for walls and slabs. In both cases, the equipment is to be rented, for the total area of 2,000 sf of walls and 2,000 sf of slabs. Overall, 160,000 sf of walls and 160,000 sf of slabs will be formed. Costs, labor productivity, and work durations are as follows:
Due to the higher weight of the tunnels, this option requires greater lifting capacity, resulting in an additional $35,000 of crane cost. There would be no difference between the two options in the quality of the concrete. Hourly wages are $21. The overhead of the project amounts to $90,000 per month. What is the most economical option?