Contract Payment and Performance Clause

Hello, My company is in the process of going thru contracts for two schools in Maryland that are private/public partnerships in which we are working the CM/Private partner. In the process I noticed the below clause in the contract and this not a typical clause I see in our contracts I wanted to see if this was typical in the industry. "It is expressly agreed that time is of the essence of this Agreement, and that the payment of the consideration herein expressed to be paid by Construction Manager is executory and strictly conditioned upon timely completion of Trade Contractors Work and proper performance of Trade Contractors obligations under this agreement. Unless otherwise agreed by Trade Contractor and Construction Manager, Trade Contractor shall bear the risk of loss of any of Trade Contractors Work (including property intended to become part of its work) and shall insure it on a 100% replacement cost basis, until such work or property is delivered to the project site and/or accepted by the Construction Manager." The concern is that payment is linked to performance or time of completion and the fact that many issues beyond our control can cause delays that should not result in holding payment for our installed work. We are a steel erection company located in Virginia and we have been in business since 2002. As a result we will not be supplying much other than labor, equipment and consumables such as welding rods in our scope of work. Thank you, Michael D. Belcher Vice-President Trinity Steel Erection, Inc.