When estimating the underground utilities portion of your project be sure you understand all of the work required and which party is responsible for each item. For instance installing new water pipe usually requires a connection to an existing system. Some utilities require that their staff do this work for a fixed fee while others require that the wet taps be performed by a limited number of prequalified contractors. If either of these requirements applies you will need to verify the costs before submitting a bid.
Pavement restoration is another potential estimating problem. Make sure that you understand all of the local requirements that may have been included in the specification by reference. Some municipalities require temporary patching of the roadway every night, even if the part of the patch must be removed the next morning to continue the work. In some cases cold patch is accepted for temporary patching, in others hot mix is required. Other towns require a temporary patch using hot mix to remain in place over a winter or for a prescribed number of months before it is removed and a permanent patch is installed. The waiting period often requires the contractor to remobilize for a small amount of work relative to the overall contract. Final patching often requires the top layer of bituminous concrete to cover an area much larger than that disturbed by the pipe trench. Municipalities often require a new top layer over the side of the roadway disturbed by construction. On some jobs the GC may take care of all final paving while you will need to provide it on others.
Other items that are sometimes vague include traffic control, temporary service, connecting or reconnecting existing buildings, and testing. Are you required to use a specific lab or are you free to pick any qualified lab?
Some sites require additional scrutiny because there may be some hidden costs involved within any special site conditions. You need to field any survey information provided to be sure that all potential interferences have been identified and appear to be accurately located on the plans. When feasible check for hidden items such as manholes buried during the last repaving job.
Owners who are putting together plans and specifications should use a checklist to review the requirements of the job and at the job site conditions. A complete and accurate description of all requirements will lead to more accurate estimates and a better working relationship.
