Terms of auto insurance policies differ so you and your fellow co-workers should check with your individual insurance company agents to see if there will be any issues with your auto insurance coverages due to the construction and non-paved parking lot you will be required to use.
Generally though there are not normally restrictions about parking in a gravel or non-paved lot in an insurance policy.
Remember that your deductible will have to be paid for any damage to you car in the parking lot, if you claim it under your physical damage coverage.
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