A remodeling company that did not use subcontractors would have quite a large full-time crew: plumbers, electricians, drywallers, masons, excavators, hazardous waste specialists, and so on. Unless the company is very large indeed, those tradesmen will have a great deal of down time. The solution for most companies is to sub out work that can't be performed by their own forces. But when a contractor subs out work, it's as important to have a written contract with the subcontractor as it is with the customer, and for the same reasons. The purpose of a detailed subcontract agreement is to make it clear who is to do what, and when. Here are the most important issues a subcontract should address. Schedule.