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Case Study - Window Trim .jpg


Cost-Estimate Challenge

 A building was under a near complete interior renovation, while the exterior upgrades were designed to look like its original 1930’s construction. The Contract windows on this historic renovation looked too modern for the Owner’s taste. The architect was asked to design a new window consistent with this era of construction. A new design was presented, and the Owner was pleased believing little to no additional costs would be incurred; they were wrong. The glazing contractor asserted additional trim required per updated design would add significant time and materials. The General Contractor presented a change order proposal for $314,170 for this work. Meetings between the Owner’s CM team and General Contractor followed trying to bring these costs down, but no progress was made. Schedule impacts quickly became a concern too because exterior glazing was on the construction schedule’s critical path. The Owner’s CM Team wanted to validate whether these costs were fair and reasonable. At this point the Owner asked Prufen to independently analyze this change order proposal.

Prufen studied the Contract’s window schedule and updated design renderings. Prufen also visited the site to review the mockups and as-built conditions. It was clear the proposed window changes would add additional labor and material costs. Prufen commenced producing a cost estimate for the Owner’s CM Team. Prufen’s completed cost estimate confirmed the General Contractor’s proposal was not fair and reasonable. Prufen presented these findings to both the Owner’s CM Team and General Contractor. The glazing subcontractor raised objections to Prufen’s labor productivity rates and material costs. Prufen’s cost estimate total was less than half of the General Contractor’s proposal. This significant disparity only hardened the General Contractor’s position, making an expeditious resolution unlikely.

Cost-Estimate Solution 

Prufen’s cost estimate was based on a detailed review of the Contract and change documents. Although the General Contractor expressed opposition to Prufen’s findings, they did not support this position with sound arguments. In response, Prufen’s recommendation to the Owner was simple: let’s go to the glazing subcontractor’s shop and observe the additional window trim being installed. The Owner liked this idea. Prufen worked directly with the glazing subcontractor to coordinate a time to visit their shop. Prufen’s cost estimator took detailed notes during the visit, which included timing different manufacturing steps. Once this data was turned into information, it substantiated Prufen’s cost estimate assumptions. The glazing subcontractor reviewed this information and agreed to reduce their change order proposal’s price.



Prufen worked directly with both the Owner’s and General Contractor’s team to successfully settle this change order at $148,544. This was a 52.70% decrease from its originally submitted $314,170 price. Prufen’s independent cost estimate analysis ensured a fair and reasonable price was paid, while its expeditious resolution kept the project on schedule. 

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