We were commissioned to perform a retrospective analysis of the cost differences between various methods for fireproofing a high rise building. The building had been constructed of structural steel with spray applied fireproofing. We studied the cost impact that would result if the building had been built of concrete, concrete encased structural steel, structural steel protected with plaster, and structural steel protected with gypsum board.
The analysis started with a detailed cost estimate developed using materials, labor and equipment costs from a national database, with costs adjusted back to the date of construction. To demonstrate the accuracy of this estimate, it was compared to actual construction costs. A detailed schedule for the project was prepared so that the cost of schedule differences could be accounted for. This schedule was adjusted for actual events, such as strikes, and to demonstrate its accuracy, was compared to the actual construction duration for the project.
This analysis found that spray fireproofing on structural steel was the most economical choice. The cost savings resulting from the use of spray fireproofing over other fireproofing methods was calculated. This was important, as there were no non-asbestos-containing spray fireproofing materials available at the time of construction. The present value of the savings was great enough to more than pay for removal of the asbestos-containing fireproofing in the present day. This analysis demonstrated that the decision to use a fireproofing material that would ultimately be replaced provided an economic benefit to the developer.