Tiny House

Casita II Tiny House | Post 013 | Plumbing Rough-in

“Adiós, boiling water…you will be mist.”

Not funny? Yeah, I know, but what better way than to start an otherwise boring post?


Actually, getting the plumbing roughed in was exciting and simple to do. I’ve taken apart sink drains and unclogged garbage disposals, but a full plumbing system initially seemed like a daunting task. By using PEX piping with Sharkbite fittings, however, it could not have been easier.

We diagrammed each place we would need hot and cold water and then did rough measurements for the length of PEX pipe, fittings such as elbows, tees, and manifolds, and faucet and shower connections.


We planned on a kitchen sink with reverse-osmosis water filter, shower, washer/dryer combo, bathroom sink, and an outdoor shower. In a more permanent setup, we could tee off the outdoor shower line and move the washer/dryer out to make more interior space. The reason for the simple diagram rather than the SketchUp model is that I wasn’t sure exactly which path the piping would take around doors, windows, and other obstacles. Before installing drywall, I’ll then accurately map out where each pipe goes in case we need to refer to it in the future for repairs or wall-mounting of objects.

Our current water source has to travel over 100 ft. downhill, then through an RV water filter (not pictured) and into a garden hose attachment. It next flows through a pressure regulator and gauge, then splits off into hot and cold service from inside the wall.

Water intake


Our EccoTemp on demand hot water heater requires 110v power and propane to run and has an interior temperature selector. To test the system, I just plugged it into an extension cord, but there will eventually be a sealed, outdoor electrical outlet above.


On demand hot water

Looking from the inside, hot and cold manifolds split to provide water to each source noted above. I figure that if there is a leak somewhere, it may be faster to remove the wall panel and shut the water off rather than run outside to the main source.

hot/cold shut-off
Laundry hot/cold

The hot and cold lines to the bathroom sink tee off to copper pipes because they go through the floor for the outside shower. Rodents like to chew through PEX and the great thing about the Sharkbite fittings is that you can connect to either material. I used some spare valves for now until we sort out how the outdoor shower will be set up.

The indoor shower has the choice of using the sprayer handle or the overhead rainfall option. We bought the shower assembly on Amazon to make sure everything would fit properly, but I’ll cover this in more detail in a separate post.

I also drilled the holes where drain pipes will eventually go and plan to put them all together during the finish plumbing phase. By the way, don’t drill through wood, insulation, and metal then look through the hole for a creepy picture…It’s not worth all that crap in your eyes!


Water Test

Once everything was complete, I hooked up the water supply and connected the water heater. When I turned the valve for the hose attachment, the system filled with water rapidly and maintained pressure consistently. There were no leaks or drops in pressure for more than one hour, so drained the lines and proclaimed success.

Lessons Learned

While Sharkbite PEX is very easy to work with and requires virtually no previous knowledge of plumbing, I ended up needing to return to Home Depot several times to get more fittings. Time and money could have been saved by buying in bulk and returning what was not needed.

Sprint 9 Totals


  • CURRENT PROJECT COST = $23,933.66


See you soon 🙂

K/R – Casita II

2 thoughts on “Casita II Tiny House | Post 013 | Plumbing Rough-in

  1. Your blog/updates are well documented and super helpful! I was building in San Diego/North County area but took a year off. Looking to start it up again and your blog is so encouraging. You guys are doing such an awesome job!

    1. Thank you, that’s kind of you to say! Let us know if you need any help on the build. I’ve got extra materials and we love meeting other tiny house people.

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