The most involved job in home bar plans is the design and installation of the plumbing. Without it, a wet bar is just a counter. The task entails cutting into the existing water line, running both hot and cold water to the wet bar and piping the drain back to the main drain of the home. Depending on where the wet bar is to be located, this job could require a lot of plumbing. The water lines and drainage will have to be brought to the bar. The best thing to do is plan where your bar will go and make the necessary adjustments to plumb it.
Step 1: Determine Water Line Path
With the bar framed, the sink and dishwasher in place but not yet connected, it is time to supply them with water and drainage. Determine the shortest possible path from the water lines and the drain pipe to the wet bar. Ideally, there will be as few joints as possible. At minimum, you will have to solder T-joints in both the hot and cold water lines, run it down to below the level of the sink and dishwasher and connect a 90-degree joint.
Step 2: Cut into Water Lines
Turn off the water to the house and have a bucket handy. With a pipe cutter, cut into the hot and cold water lines precisely where the T-joint will go. Fit the T-joints in place and solder the connection. The T should point to the ground.
Step 3: Make Holes for the Water Lines at the Bar
Whatever the thickness of the copper pipe, drill 2 holes in the wall through which to run the water lines. They should enter the bar area close enough to the sink and dishwasher to make for easy installation.
Step 4: Run Copper Water Lines
At the newly-installed T-joints, run a length of copper pipe from each to the point where they will turn and enter into the bar area. Solder the connections at the T-joints. Solder copper 90 joints onto the open ends, pointing them towards the holes in the wall.
Step 5: Run Copper into Bar Area
Run enough copper pipe through the wall and into the bar area. Solder at the 90 joints on the outside. In the bar area, solder a double stop fixture onto each line to accommodate both the dishwasher and sink.
Step 6: Attach Sink and Dishwasher
Using the flexible stainless steel supply lines, connect both the sink and the dishwasher to the hot and cold water supply, making sure the connections are sealed.
Step 7: Cut into Main Drain
At the main water drain, cut into the pipe, making a 2-inch hole with a hole saw. Attach and seal a saddle T-joint onto the PVC drain.
Step 8: Run Drain Pipe to Bar
Using 2-inch PVC pipe and the necessary connectors, run the drain pipe through the wall and into the bar area. Glue and seal thoroughly each PVC connection point. Connect a PVC splitter once the drain pipe is in the bar so both the sink and dishwasher can attach to it. Connect the drains for both to the splitter.
Once everything is in place and you are sure the connections are well soldered and sealed, turn the main water back on and test out the water system of your wet bar.