Why it might workNew construction might be challenging— taking empty space from excavation to finishing. But even big remodeling projects can seem doable because the space is already defined. Some DIY skills will help, of course. But planning and common sense could get you through. How hard could it be to coordinate an electrician and a plumber, a delivery of drywall and a load of cabinets?
But the main incentive is money. Manage the project and you eliminate the GC's cost of doing business— an office, shop, truck or two, lights, computers, tons of tools and workman's comp for the crew among other expenses. And handy DIYers can tackle a lot of the finishing work, some sanding and painting, maybe the drywall and the trim, which would eliminate a subcontractor or two and save even more money.
The idea becomes even more appealing when you run the hypothetical numbers. Materials often run only 40 percent of overall job costs, and even if subcontractors cost almost as much there should be at least 20 or 25 percent to capture. If you can handle demolition to begin with and painting to finish, it might be 30 percent or more. On a $30,000 remodeling job that's nine grand, a powerful incentive. Some DIYers give themselves another five percent or so, figuring a GC will mark up lumber and everything else that's delivered. If there's no GC and the DIYer goes to the lumber yard, total savings might be 35 percent or more. But that's the first of several catches.
Why it might not workA material markup is considered a handling fee by most contractors. They figure out what you'll need, order it and pick it up or have it delivered. Sounds simple enough for a DIYer, except you may get the order wrong, particularly with technical trades like plumbing and wiring. And the lumber yard may not give you the privilege of picking through the pile or returning twisted timbers. And suppliers generally won't give a one-time buyer like you the discount they give contractors who buy year round.
If the job requires subcontractors you'll have to find them, describe the job in their language, evaluate their estimates, negotiate prices and draw up agreements. On remodeling jobs that need subs, the GC does all that, or has a crew already.
You'll also have to coordinate their schedules, which can get tricky. For instance, when framing is still open plumbers and electricians have to be there to rough in lines. After the walls are closed they have to come back again to install fixtures. If they can't come back when you need them, the job stops. A delay with the new cabinets? The plumber reserved a day to finish but now is on another project for a week. No plumber means no fixtures so the electrician has to find a new time to wire the dishwasher that's sitting in the garage.
And on substantial projects, say, that involve structural alterations, you'll need a permit. To get one you may need a set of plans. And as the job progresses you'll need to deal with one or more inspectors. There's a lot to keep track of. So if you haven't been your own GC before, try it on a modest project— a few days instead of a few weeks, one room instead of several. After all, if being a GC was easy, almost everyone would do it.