Meeting the plumbing and electrical requirements in your garage can be a challenge, but not an insurmountable one by any means. You’ve got options that will make sense for your project. Here’s an overview of how you can supply your garage with the power and water you need.
Plumbing in your Garage
With any luck, the person who built your house had the foresight to run a hot and cold line to the garage. If so, the rest is easy. Water lines can be run above grade to a bathroom, wet bar, sink, etc. The lines should be insulated to conserve energy and to prevent cold lines from sweating and dripping. Running them overhead makes the most sense, but try to keep them in heated space to avoid freezing.
If lines are not in place, it will probably require going through concrete to get there. In most cases, you’ll want to bring lines to the closet point, and then run them from there as suggested above. This will cost less than tearing up the entire garage floor. Of course, if you’re planning a new floor, then the job is easier.
Another option is to bring a feed from the water line entering your home to the garage. Then separate it into hot and cold lines. For heating, a tankless water heater installed in a closet or under a countertop is great choice.
Getting rid of waste water is a bigger challenge. Your best option is to tie drain lines to the main line heading to the sewer. If you have a septic tank, it might be easier to run the drain line to the outsides and tie it into the drain line before it enters the tank. You’re probably going to have to bust some concrete no matter what you do, and this might turn out to be one of the most expensive parts of the job.
One alternative, if there’s enough headroom in the garage, it to install a subfloor over the concrete with 2”x4” or 2”x6” construction. The hot and cold lines and drain pipes can be installed in the space created by the subfloor, reducing the amount of concrete work required.
A plumbing contractor with experience in garage conversions will be a real asset in figuring out the most cost-effective way to handle the drains job.
Electricity in your Garage
Your garage probably already has power. There are two question. First, does the electrical panel have enough capacity to accommodate the demands of the garage? If it’s a 100 amp panel, the answer is almost certainly no. Increasing the panel to 200 amps will probably be needed, especially if you plan to run equipment that uses a lot of power such as an electric storage tank water heater, a welder or a large space heater.
The second question is whether enough circuits were run to the garage. The answer here is probably no too. Check your electrical box labels. More than likely, you’ll want to run another couple of circuits for the garage to reduce the risk of overloads and circuits tripping.
Another option is to have a separate electrical panel installed in the garage. It will give you the most flexibility and will make it easier to run power to where it is needed.
Consulting an electrician about all these issues will give you the answers you need. Following their advice will ensure you’ve got sufficient, safe power for all your garage purposes.