Step 1: Pry up the Floorboards

Mark the measurements for the drain circle.

Unscrew the screws in the floorboard and pry up the floorboard.

Use a reciprocating saw to cut out the floorboards.

Tip: To get close enough to the wall, slightly bend the cold blade before cutting. Once you use the blade, it will be too hot to touch.

Step 2: Cut the Pipe

Underneath the floorboards you will be able to see the drain coming from the back of the tub, and a drain vent that goes up the wall. There was a second drain from the old vanity and that is the one where the T-pipe will go. Lay out the pipe at a 45-degree angle and mark the joist before you cut it (Image 1).

Use a large right angle drill with a forstner bit to make the cut. This is also known as a Super Hole Hawg (Image 2).

Mark the drain pipe, and cut through it with a reciprocating saw.

De-burr the drain pipe with sandpaper.

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    Image 1

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    Image 2

Step 3: Attach the T-Pipe to the Drain

To do the solvent weld, prime the inside of the T-pipe and the outside of the pipe with an all purpose pipe cleaner (Image 1). Once that dries, you are ready for an all-purpose cement.

Note: There are many types of plastic pipe: PVC, CPVC or ABS.

Place the T-pipe onto the drain and into the hole you cut (Image 2).

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    Image 1

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    Image 2

Step 4: Cut the Old Copper Pipes

Reconfiguring of some copper pipes had to be made to make room for the trap. Hard copper will be used to run the line around in a horseshoe shape in order to get it out of the way of the trap, and copper will be used to run the lines up to the supply lines of the shower

Note: There is not a lot of difference between hard copper and soft copper. Soft copper is bendable and can work around corners without having to put fittings in.

Note: Make sure to turn off the water before cutting the pipe.

Cut the old copper pipes with a close quarter pipe cutter.

Step 5: Dry Fit the Assembly and Solder

Dry fit the new copper supply assembly. You need to make sure that the drain pipe falls 10" on center (Image 1).

Apply flux to the copper before soldering.

Solder the pipes together, heating the fitting, not the solder (Image 2).

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    Image 1

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    Image 2

Step 6: Cut Holes and Run the Pipes

Use the Super Hole Hawg to make the holes in the studs for the soft copper to pass through.

Use a coil tube bender to make sharp turns (Image 1).

Cap off the end of the run (Image 2) and turn the water on to check for any leaks.

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    Image 1

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    Image 2

Step 7: Install the Valves

To install the valves, you need to decide on how you want to arrange the controls.

Put in a backer board between the studs to mount the mixer valve. Use a framing nailer to secure the backer board in place.

Measure in 22" to center the valve.

Set the valve behind the backer board which will be secured with metal plumber's tape.

For the showerhead, solder a threaded elbow with ears onto the supply line, then secure it to the backer board with screws.