How would you vent and run water in this basement bathroom?
Homeowner here. Finishing a large basement, including a big master bath. Builders roughed everything in under the slab, and I framed it and am running electrical. Was planning to hire the plumbing, but between the quarantine and plumbing estimates I got, I'm considering doing it myself. I've posted a couple photos and will describe my issues below. Would appreciate advice and how you'd vent and run water to the lavs in this setup. Thanks!
1) Builder put a main HVAC trunk directly above lav 2. I dropped the ceiling to just barely below it while framing, but I hadn't considered plumbing at the time. Trunk extends out several inches on either side of the header, so vents and PEX lines to lav 2 can't come straight down. Either they need to run through the framing on either side or I need to frame a bulkhead on the wall behind the bathroom. That area is like an entryway or sitting room with entrances to the master bedroom, bath, and a closet.
2) Builders left a capped 1.5" vent above lav 1 and another on the far side of the basement about 25 feet away -- perhaps for lav 2. It's near the ejector pit, but that already has its own capped vent left on the wall right next to the waste line. Can both lavs (and by extension, the whole bathroom -- two lavs, toilet, and separate tub and shower drains) be vented by the line above lav 1? Either way, how would you deal with that stupid HVAC trunk above lav 2? Can a 1.5" vent line realistically be run through the framing above the doorway there to serve lav 2...or is a backside bulkhead a better idea?
3) Builder left 3/4" PEX stubs above the toilet and shower, but none above either lav. There are 1/2" lines running in the joists above lav 1, I believe from the laundry to the kitchen on the main floor, but no stubs left. Would you tap into that 1/2" line to supply one or both lavs, or would you tee off one (or both) of the sets of 3/4" stubs that were left elsewhere in the bathroom? And again, given the obstacles around lav 2, how would you run those lines? Parallel to the vent after figuring that out?
Thanks for any advice!
Comments (9)
Nick Abel
4 years agoRelated Discussions
Basement Bathroom Sump Pump
Comments (0)We just recently purchased a home that has a fininshed basement. The full bath downstairs has a sump pump to send the sewage to the septic system. There are two things happening and I can not figure them out. I believe they may be related: 1) When we flush the toilet downstairs, it flushes pretty good and the water is flowing to the spetic. You can hear it go through the line (do not ever hear the pump). After you flush it, you start to smell sewage in the garage near the pump, and worse in the basement (septic line runs above drop down ceiling) and closet (where the line goes to septic). It does not smell in bathroom. This is the only time it smells. This line connects to the main sewage line. Why is it smelling? There is no leaks. The sewage vent goes to the attic where it make a right turn and connects to original sewage vent. 2) At randon times through the night, we here this knocking sound. We have concluded that it is the water line. It does not do it when anything is running. It does it mostly at night when things are off. I have shut off valves and when I shut off the basement bathroom water supply, it has not happened for two nights. The knocking sounds like it has a restricted flow, but it has a destintive pattern. Does the sump pump require water from the main line? The knocking takes about 20-30 seconds when it occurs. I have yet to notice the toilet running when it makes the noise, but I have not checked since it has not happened since we shut off the water. Any help would be great!! Thanks Chris...See MoreMildew on non-vented bathroom ceiling. How to ventilate?
Comments (6)A typical bathroom fan only exhausts so it can't provide ventilation air (i.e. outside air) but it removes moisture laden air and pulls in dryer make-up air from the adjacent room. There are bathroom fans that do provide outside make-up ventilation air that passes through a heat exchanger. As a temporary solution, you could open the window a bit or clean and repair the ceiling so it is very smooth and paint it with a semi-gloss vapor barrier paint with a mildew resistant additive. It wouldn't hurt to wash it every few months too. Flat or textured paint would speed the growth of fungus. But I suspect you will need to replace the ceiling and that is the time to install an exhaust fan. Of course you could install a simple exhaust fan through the wall near the ceiling with an humidistat and timer....See MoreWha my kind of cost to expect for running water for basement bathroom?
Comments (2)Around here you can figure $1000/fixture for rough-in as part of the plumbing bid. As a later add-on I would expect it to be more. Significantly less if the waste and vent lines are already done and it's only for supply lines, unless the walls are already closed up. So, as always, it depends....See MoreUgliest Bathroom in the World: Basement Bathroom Renovation
Comments (2)are there bedrooms down there as well? if someone will be using the bedroom in the basement, then they will want a decent bathroom to go with it. 6 inches really isn't worth the hassle of taking down or moving a wall. A foot, maybe, 6" ? no. once you put on the wall or tile, you've got maybe 4" total. Maximize the space by choosing a good vanity w/storage, and possibly building a niche into the wall for additional storage. (use the area between the studs as a built in cabinet) using a prefab shower is fine, but pick a decent one as opposed to those flimsy acrylic pieces. you don't say want the resale value is, so i have no way of knowing how much you should invest. You say you bought mid-range, but I don't know what else you need to redo. anything under a 15% profit really isn't worth it. as for fitting it over the existing drains, usually you will need the new drain cover. if the drain needs to come up, there are extensions. I would advise your husband to do some research on how to fit those into an existing bathroom. If he's handy and can build his own slope, mortar bed and waterproof the shower, then he could prob tile it himself. Just depends on how much work you want to do and what the return is on what you choose. by the looks of what you have there currently, you may have some water damage underneath all the mess. Tear out what you can and then determine what you need to do....See More
User
4 years agoBruce in Northern Virginia
4 years agoBased on my experience, DWV is a lot more complicated to design than it seems. Don't feel bad if it seems like a lot to figure out.
Two bathrooms on the same level can share a single horizontal wet vent, so you might be able to use a single vent. However, there is a formula for the vent size, and it seems like you might need a 2" vent for that many fixtures. Here's one example from the Terry Love Plumbing forum, where they discuss these questions in detail. https://terrylove.com/forums/index.php?threads/use-of-aav-for-basement-bathroom.66692/
If you have 3/4" PEX stubs for hot and cold you will have no problem feeding all the fixtures. The simplest DIY solution is to buy a copper or stainless steel PEX manifold similar to this one. https://www.pexuniverse.com/sioux-chief-5-port-pex-copper-manifold-w-valves-672xv0590 The 3/4" input goes into two manifolds (hot and cold) and all the 1/2" pex lines go out to each fixture. You can also buy a manifold with an open ended 3/4" connection so that you can daisy-chain them together.
I bought one of the 14"x14" metal covers from HD to provide access to a stud bay, and then strapped the two PEX manifolds on boards between the studs. It was a little difficult to get it all to fit, but it is now very convenient to shut off hot and cold to each of the fixtures. This is a picture of the back of the manifold while the build was still in progress. It did look neater when I was done.
Bruce
PROProSource Memphis
4 years ago
PROCharles Ross Homes
4 years agoNick Abel
4 years agoCherie
4 years agoBruce in Northern Virginia
4 years ago
Jake The Wonderdog