Hall bathroom remodel

[Nancy0]

Good Morning all- I am in the process of remodeling our hall bathroom and have a few random questions. It is a tub/shower combo and I have purchased delta mixing valves for the shower and a kohler tub. Bathroom is above a crawl space.

So my question is:
Why is it not common practice to install a shutoff valve on the water line(s) to the mixing valve? Is there any issues with doing so? I am also planning on putting in a recirculating pump down stream on the hot line for the one day when we get a tankless hot water heater.

Drain lines Can you just put in one vent for the entire bathroom? What is the maximum distance the vent can be from the source assuming a horizontal run (yes slightly downward)? Are there different requirements with a septic tank vs city sewer?

I’m sure I'll have more so thank you in advance for your help!

Nancy

[Terry]

The rough-in valve for the Delta Shower control can be ordered with shutoffs. Many plumbers order the standard valve and just shut off the entire home if needed. They tend to go at least ten years before any servicing would need to be done.

Every plumbing fixture needs a vent. You can tie those vents together at 42" above the floor. Being on Septic or Sewer is the same difference. It's all going downhill.

Here is a nice link to Bert Polk's plumbing tips

[jadnashua]

Shutoff valves can be installed, or you can buy a shower valve with them in it. If you are going to the trouble to install them, then placement in an easily accessable location is probably better - to get to the ones in the valve, you have to remove the cover, and most servicing to the valve doesn't require that, so most of the time, people don't even realize they are there.

EACH trap needs to be vented, but there are ways to combine those individual vents to limit how many penetrations you need in the roof. The basic rule for the minimum height of combining vents is you can combine them 6" above the flood plane, or 42" above the floor, whichever is higher. It's often easier to do this in the attic, but not always. The distance from the trap to the vent depends on the diameter of the drain line - the larger the drain line, the futher you can be from the vent.

[NancyO]

Thank you for the help! I have come up with more questions now that the wall board has been removed!

Tub/shower combo drain.....
I have an existing vent (currently unused) on the opposite side of the bathroom from the where the new drain will be, can I join up to it if I start going upward at 5 ft from the new drain( 2" pipe"? Does the 5 foot run need to be "downhill" 1/4 for every foot or should it be perfectly horizontal until it encounters the vent? Trying to use what I have so that I don't end up with any extra holes in the roof! Also do you have any tricks for going through headers for the pipes?

Toilet.. Can the toilet have a 3 foot vertical run (with vent coming off it) prior to running downhill horizontally?

[cacher_chick]

All of the pipes must be pitched at least 1/4" per foot.
Vents must be vertical until they are at least 42" above the floor.
If the space above is an attic, the vents can be tied together there so that only one pipe needs to go through the roof.

[jadnashua]

Because a vent might collect condensation, rain, or snowmelt, it MUST slope down to the drain ALL THE WAY. Otherwise, it is likely to eventually fill up with water and become useless.