Because of Federal aid most Iowa DOT projects that have DBE goals will also have predetermined wages set for that project. To determine if a project has pre-determined wages look at the cover of the estimating proposal:
Farther back in the estimating proposal there will be a listing of the specific wage rate.
The Iowa DOT has posted all the wage decisions on its website at: http://www.iowadot.gov/Construction_Materials/contract_admin.html
Certified payrolls must be submitted weekly as you work on a project. You can use your own accounting software or one of the following forms provided by the Iowa DOT:
On the wage decision each labor classification will have a minimum hourly rate for the pay rate and fringe benefits. If you pay for some employee benefits (health insurance, pension, vacation, holidays, sick leave) you can deduct the cost of providing that benefit from the required fringe benefit rate. If you don't already deduct this cost I would strongly encourage you to do it. To help explain I found this section out of the US DOL Davis-Bacon Resource Book that is easy to understand:
Also fringe benefits paid in cash are subject to the added costs of payroll burden (FICA, FUTA & SUTA, General Liabilty, Workers Compensation Insurance). Plus paying for a vacation expense at the end of the year will delay that expense and help your cash flow.