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Gabety
Oct 17, 2008, 08:42 AM
I am constructing an additional area on my heated garage/shop in Eastern Illinios. It will be of post frame and slab floor. In this additional area I wish to have a "utility" restroom. I really have now idea on roughing in the plumbing I intend to use a 3" line to my septic tank. Some questions I have are:

Does the toilet drain extend above the floor without a flange to be cut down and fitted later?
Same with a sink drain? I intend to install a free standing sink like found in a janitor's closet.

Plus combining the drains to the go to the septic along with venting and vent's place in relation to fixtures. Cleanout? Is it possible to vent through a wall rather than through the roof?

I'm trying to learn so all knowledge is appreciated. Thanks.

massplumber2008
Oct 17, 2008, 03:52 PM
3" drain line is fine.

You will need a FULL SIZE cleanout wyed off with a 45 degree fitting and brought to grade just outside the foundation (within 18" or so) before entering the septic system.

If wet venting is allowed in your area then this will be pretty simple job for you. Simply run that 3" pipe directly to the toilet elbow and stub above the ground for now. Be sure to wrap the 3" pipe as it comes out of the ground with either some cardboard and tape or some foam wrapping so that when pulled after concrete is poured/hardened you can remove and still have about a 1" space around the pipe. You will use an inside cutter to cut the pipe down later.. or you could just DRY FIT the stub up piece for now and just pull it out and cut it later AFTER flooring is installed.

Directly behind the toilet elbow... say 3 or 4 feet you will want to install a 3"x2" WYE fitting... in my area you roll this above centerline of waste line, and in some areas you come off flat with this wye... and run this over to the sink. You will stub this pipe out of ground and install a 2" cleanout just after coming out of the floor. Then you will install a 2"x1.5" sanitary tee fitting to pick up the sink at about 18" off finish floor to center of the tee fitting.

Then you will continue to run this 2" pipe up wall and oput the wall as a vent as long as no windows or similar within 10 feet or so of wall penetration....this would then be brought to between 12-24" above roof depending on where you live.

If no wet vents allowed in your area then you will take the 3"x2" wye and run that to near the sink and you will install another 3"x2" wye just behind the first 3"x2" wye and run as described earlier for sink drain. Then you would combine the 2 vents at about 42-48" off the floor and then run a single 2" vent as described earlier...

When you come out of the ground use a LONG SWEEP ELBOW for sink/vents...

Use only long sweeps undergound or 45 degree fittings.

That should get you started thinking a bit... ;)

Let us know if have any questions... glad to help!

MARK

mygirlsdad77
Oct 17, 2008, 05:24 PM
Mark is right, but I would definitely either tie the vent into an existing vent at least six inches above the highest fixture in the house(minimum size 2inch) or take it out separately through the roof. Wouldn't recommend venting out a wall.

Gabety
Oct 17, 2008, 08:14 PM
That should get you started thinking a bit...


You got that right! I'm sure I'll be back. Thanks guys.

Milo Dolezal
Oct 17, 2008, 08:42 PM
Yes, you can have toilet pipe stick out few inches, than cut it off above finished floor. Then, buy ABS closet ring that fits either inside 3" pipe or outside.

As posted above: don't vent through the wall

speedball1
Oct 18, 2008, 07:38 AM
I really have now idea on roughing in the plumbing I intend to use a 3" line to my septic tank.Most bathroom groups are roughed in like this.
Toilet connects to sewer main. Lavatory connects to toilet drain and runs a vent off the top the stubout tee out the roof or wall if the roof isn't a option. The toilet wet vents through the lavatory vent. This is a normal rough in and is acceptable both by local and state codes and also The Standard Plumbing Code Book in 90 percent of the country. Check your local codes to make sure you're not in the excluded 10 percent..

Does the toilet drain extend above the floor without a flange to be cut down and fitted later?Yes, the toilet stubup extends above the floor with a closet wrapper around it so you can either mount a inside or a outside flange when the floor's poured.

Same with a sink drain? I intend to install a free standing sink like found in a janitor's closet. you will come off the toilet drain line with a 3 X 2" wye to pick up your sink. You will then take it over to the wall you wish to mount the sink on and stub up in the wall.

Plus combining the drains to the go to the septic along with venting and vent's place in relation to fixtures. Is it possible to vent through a wall rather than through the roof? You will run a vent off the top of the 2 X 1 1/2" Sanitary Tee that you pick up the sink with. You may vent out of the wall as long as it doesn't terminate directly beneath any door, window or any ventilation opening. It shell not terminate within 10 feet of such a opening unless it is 2 feet above such opening. It shall also be screened and not terminate under the overhang or soffet of said building.

Cleanout? A 3" cleanout should be installed not over 18" out from the foundation and brought to grade. Good luck, Tom

Gabety
Oct 20, 2008, 08:22 AM
Simply run that 3" pipe directly to the toilet elbow and stub above the ground for now. Be sure to wrap the 3" pipe as it comes out of the ground with either some cardboard and tape or some foam wrapping so that when pulled after concrete is poured/hardened you can remove and still have about a 1" space around the pipe. You will use an inside cutter to cut the pipe down later.. or you could just DRY FIT the stub up piece for now and just pull it out and cut it later AFTER flooring is installed.


Could you explain what the 1" space would be for around the pipe and after leaving that space is it filled in when fittings for toilet in place? Which also brings to mind anchoring the toilet to a concrete floor. How is this done? Just with the flange? It would be pvc also?
Is this space left from wrapping pipe also necessary around the sink. I like the idea of dry fitting the stub up since I don't have an inside cutter and don't want to purchase one if not necessary. The dry fit would just pull loose from the ell underground?

I intend to use sched 40 pipe under the slab. My septic line is sched 26? I think and 4". What type of fitting matches these two different pipes?

massplumber2008
Oct 20, 2008, 12:21 PM
Gabety...

The 1" space is so that when you pull out the DRY FIT stubbed up pipe you can cut the pipe and install the flange so that the flange fits between the pipe and the concrete. Without the space the flange fitting could not fit over pipe and sit down lower than the concrete floor.

You take measure and install the pipe/flange AFTER the tile floor is set(cut tile same hole size as hole in concrete). Here, flange sits on top of finish floor... then use 1/4" masonry drill bit to drill holes through tile and 1 inch or so of concrete floor and then screw flange down through TILE FLOOR and into plastic anchors....or could also use TAPCON screws...Here, you buy proper masonry drill bit and tapcon screws, drill holes and screw right through tile and into concrete floor (1.5" tapcon screws will be fine here).

I like to leave some room around all pipes coming out of the floor but it is not a requirement!

To connect your pvc to your schedule 26 pipe you should just need to buy a FERNCO COUPLING (see picture). This type coupling is made exactly for this tranbsition. They are not to be used above ground!

Keep 'em coming...

MARK

mygirlsdad77
Oct 20, 2008, 03:39 PM
Any and all pipes poured in concrete must be wrapped. Sink drains and the like only need minimal wrap. Just enough to keep concrete from coming in contact with pipe. Showers and toilets have the one inch gap so you have room for closet flange or shower strainer.

Once again. Yes do one single wrap for your sink drain and any other drains coming out of the concrete.(many more wraps for showers and toilets)

Gabety
Oct 22, 2008, 01:08 PM
Good stuff guys. It's so much help. Today I have dug up my septic line. I have a 1 foot 3 inch drop over 22 feet to the septic line. Is the rule of thumb 1/8 to 1/4 per 10 feet of pipe?

Also for future use I may install a drain line for shower stall. Is it OK to put a trap under slab?

mygirlsdad77
Oct 22, 2008, 03:05 PM
Yes, you need a trap under slab for shower.
No, 1/8 to 1/4 per ten feet is not right. It should be 1/4 inch per one foot(three inch pipe) or 1/8 inch per one foot(4 inch pipe or larger). But you do have plenty of grade with 15 inches in 22 feet. Will work just fine. May be a little oversloped if anything. I would have used a couple 45s or better yet 22 1/2s to get a proper slope. But like I said it will be fine.

Thanks for the update, and please keep us posted.

speedball1
Oct 22, 2008, 03:51 PM
Also for future use I may install a drain line for shower stall. Is it OK to put a trap under slab? Dad should have mentioned that you will have to run a separate vent for your shower unless you wet vent it by connecting to the lavatory drain line. Good luck, Tom

Milo Dolezal
Oct 22, 2008, 04:46 PM
Required slope is: 1/4" per foot for 3" pipe and it is 1/8" per foot slope for 4" pipe. But you have plenty of slope...

Some plumbers do install trap under slab, some don't. I would probably suggest to put it in. Let the raiser pipe stick out few inches from finished floor and put a cap on it. This way, you will be all set when ready to install your new shower...

mygirlsdad77
Oct 22, 2008, 05:14 PM
Good stuff guys. It's so much help. Today I have dug up my septic line. I have a 1 foot 3 inch drop over 22 feet to the septic line. Is the rule of thumb 1/8 to 1/4 per 10 feet of pipe?

Also for future use I may install a drain line for shower stall. Is it ok to put a trap under slab?

Thank you milo for backing up my grade per foot advice.

Speedball is also 100 percent correct in saying that you must make sure your shower p-trap is properly vented. All depends on your layout. Im sure one of these guys can give a picture diagram of wet vent and or fixture vent.

Milo Dolezal
Oct 22, 2008, 05:37 PM
thank you milo for backing up my grade per foot advice.

Speedball is also 100 percent correct in saying that you must make sure your shower p-trap is properly vented. All depends on your layout. Im sure one of these guys can give a picture diagram of wet vent and or fixture vent.


Ooops... I completely missed your response ! Sorry about that... Of course, you said all that I had to say. At least we know that we think along the same lines. Credit goes to you !

Ps: I was going to leave you positive feedback - but that "..reputation..." comment prevented me to... :D

mygirlsdad77
Oct 22, 2008, 05:48 PM
Ooops... I completely missed your response ! Sorry about that...Of course, you said all that I had to say. At least we know that we think along the same lines. Credit goes to you !

Ps: I was gonna leave you positive feedback - but that "..reputation..." comment prevented me to ....:D

First off, thank you. I think we do think a lot alike.

I am new to this game, and I don't understand exactly how this all works. I try to leave people (agree)comments and it says I have to spread it around. I have not set my profile not to take comments(agree or disagree). Im assuming it does it on its own.


Tom can you please help me adjust my profile so that I can still accept comments?

Gabety
Oct 23, 2008, 11:43 AM
THis maybe my last question. It was said to put in a cleanout within 18 inches outside the foundation. I got the clean out and I am now putting in the line after digging the trench. My question is, do you leave the clean out buried a few inches? I'd hate to break it when mowing also the white pvc isn't UV protected from sunlight is it?

speedball1
Oct 23, 2008, 12:29 PM
THis maybe my last question. It was said to put in a cleanout within 18 inches outside the foundation. I got the clean out and I am now putting in the line after digging the trench. My question is, do you leave the clean out buried a few inches? I'd hate to break it when mowing also the white pvc isn't UV protected from sunlight is it?

You know you can bring it up to grade and put a recessed clean out cover,(see image) in the tee, but it's OK to bury it if you mark the spot on your house. Good luck, Tom

mygirlsdad77
Oct 23, 2008, 03:13 PM
I would keep it at or above grade. If you put it under ground and mark it somehow, then this is great for you, but 50 years or so down the road, the next homeowner won't know where the cleanout is. If you do put it above grade, there are many many ways to hide it (lawn ornaments, decrative brick, so on so forth), Just my advice, since I have spent countless hours probing and digging to find outside cleanouts.


Glad to hear your job is coming along smoothly.



p.s. you should have the cleanout within 18 inches, but you can put the cleanout as close to the house as possible, this way it is just one more thing to weed eat around in stead of mowing around. In this case you let it stick up several inches so you don't have to worry about running it over with the mower. And as far a sunlight, it will be just fine. May fade a bit but that's about all.