Frost protection for outdoor shower
AdamPNW
| Posted in General Questions on
I’m planning an uninsulated outdoor shower that will be attached to (but outside of) the building envelope of our new construction slab on grade home (12” frost depth). Laying sub slab plumbing now, and wondering what’s the best way to frost protect the water supply to that shower
Option1: run a frost protected sillcock through the envelope? Would supply lines then connect with a garden hose fitting?
Option 2: run supply under the footing below frost line and connect to a frost protected hydrant. Again a garden hose connection to supply lines?
Is there a standard technique I’m missing?
thanks,
Adam
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Replies
Install a shut off inside the envelope and leave the shower valve open. If still worried, install a Schrader valve in your supply lines and blow them out before winter comes.
Thanks Nynick, maybe I’ll go with that.
Put all the plumbing on the inside.
You can get ball valves with stem extension or maybe a even standard shower valve with longer handles might work. Feels like there should also be something specifically for outdoor showers that has this.
The only thing outside would be the shower head, angle the feed to it slightly so it drains.
Same for the p-trap, inside the house with a horizontal run to the shower drain. Another option is putting outside a bit deeper into the ground or with some rigid above it.
You could also use a smart shower valve like moen if you didn’t want the stem extension going through.
https://www.build.com/product/summary/1247218?uid=3705255&jmtest=gg-gbav2_3705255&inv2=1&&source=gg-gba-pla_3705255!c1709211100!a66212960309!dm!ng&gad_source=1&gclid=EAIaIQobChMI7Y3Qx8m7hgMVuBitBh0L0gc8EAQYAiABEgKVuPD_BwE&gclsrc=aw.ds
Since you're shutting it off, you can use regular hose bibs, not frost-free (Although your local code enforcement may require that they be frost-free). Put a male hose adapter on the inputs to the shower mixing valve, and connect them to the hose bibs with washing machine hoses. (I like stainless steel braided.) Put inside shutoffs on the hose bibs.
At the end of the season, shut off the water inside the house. Disconnect the hoses from the bibs. Put a garden hose Y on the two hoses, then an RV blowout adapter (like this: https://www.amazon.com/gp/product/B002XL2IEA?th=1 ) onto the Y and blow out the shower with compressed air.
I like to leave the hoses connected over the winter so I put plugs in the ends to keep things out, like this: https://www.amazon.com/gp/product/B003VB0YRE
Basically this is how an RV is winterized, on a smaller scale.
My shower just drains into the ground. Your plumbing code may not allow that. If you have to drain into a sewer you have to protect the trap from freezing. Indoors you'd fill it with RV antifreeze, but unless you have a way to keep rain out that wouldn't work outdoors. One way would be to have a raised floor with the trap accessible underneath, and a plug in the trap that can be removed for the winter.
Perfect, thank you all for the advice!