Bathroom trap sizes and fitting selection...

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Reach4

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Tub drain is off how much, and which way?

Blue-lined wet vent pipe from lav is OK at 10 ft, but should keep the 1/4 inch per foot slope. I don't know if there is a length limit. I think steeper would be OK too.
 

hhcibtpaun

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Tub drain is off how much, and which way?

Blue-lined wet vent pipe from lav is OK at 10 ft, but should keep the 1/4 inch per foot slope. I don't know if there is a length limit. I think steeper would be OK too.
Thanks for the reply.

I am going to redo the tub drain. The length is about two feet from the trap to the horizontal combo. Hoping I can get the 1/4" drop per foot. The 10 inch pipe from the lav will probably end up horizontal.

Thanks...Mike
 

Reach4

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While I am not following the problem, I think shower base in concrete video could possibly apply to a tub drain.

I was wondering why you did not cut the current trap arm, apply the tub drain, and then deal with the offset downstream a bit.
 

hhcibtpaun

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I am confused now :). I may not have properly conveyed my concerns.

1. Is it ok if the 10" pipe coming from my lav is not sloped at 1/4" per foot.
2. Using the 1/2 T-Waste kit connector coming off the drain into a 2" trap will bring the bottom of my trap to about 1/2" under the joist. Not sure if a 1 1/2" trap would help (not drop as low). If a 2" trap is still the best for avoiding clogs, then I will go with 2". Worst case I have a little panel in my ceiling below the tub.
3. For the cover plate on the tub, is there a benefit to a 1 hole or two hole cover plate?
4. For the drain is a twist drain or one of the pop up things preferred. Not sure I can use a trip lever with the 1/2 T waste connector.

Hopefully that clears things up....or maybe I made it worse.

Thanks...Mike
 

Reach4

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1. If it slopes at 0 inches per foot, no. If it slopes at 1 inch per foot, I think yes, but somebody may think differently.
 

hhcibtpaun

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I have been trying to see if it was ok if I could not get the 1/4" slope on a 10 inch run. Earlier I found this thread:


and was going off this statement:

Normally there is a built in angle to the fittings.
I wouldn't worry if it's only 12".

I am coming out of a 90 bend, so there may be a built in angle, but going into the horizontal combo, not sure that has a built in angle??

Thanks...Mike
 

hhcibtpaun

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Hey Folks,

I am seeing the light at the end of the tunnel. I am finishing up the drains in my little project. Currently I am working on the Kitchen Sink Drain that drops into the basement. I am trying to get around some existing plumbing, a window and some electrical work. The joists are getting in the way too. I have come up with two options, and was wondering if a few folks could comment on the best path forward.

When I first started mocking things up I came up with this.

This first picture is a short run from where the sink drain will enter the basement. Th pipe is probably 7 or 8 inches and I cannot guarantee it has a slope down.


straightExit.jpg


I then moved to this.

steepAngle2.jpg


I am thinking that angle on the right is too steep? Water may move faster then solids?

So, I tried a second attempt. On this one, coming off of the sink I added a street 45 which can almost guarantee I get some slope:


45exit2.jpg


Then to lessen the slope on the other pipe, I tried this:


shallowangle2.jpg


I am thinking this may be the better way to go. Although I have a straight drop, I have a lot of pipe at a better slope? I assume that adding the 45 where it comes off from the floor is not problematic. I always figure fewer connections is better, but slope probably trumps that.

Any thoughts would be appreciated.

Thanks...Mike
 

hhcibtpaun

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Hey Everyone,

While I have been working through my drains I started looking at my vents. Before I started changing things there was only one vent that came out of the main stack. It was like 2.5" galvanized. With my whole redo I was going to run 3" PVC through the roof from the soil stack and that would be used to vent the toilet, tub/shower and lav.

I also planned to have second vent (2' pvc) for the laundry sink, washer and kitchen sink. this would be 2" until it hits the attic then i would up it to 3" through the roof.

I have decided to get rid of my slate roof and get new asphalt shingles, so I can get all new collars for the vents and cut my new vent in through the roof. Currently, the vent that pops through the roof is way down low and within a foot of the edge of the roof. Looks kinda dopey. I was wondering if I could connect the vent for the toilet to the vent I ran for the kitchen and basement plumbing, then just have one vent pop through the middle of the roof, or just keep the two.

From a fixture unit perspective, it seems like I could do it, but is it better to have the two "systems' separated and just have a larger vent volume for both?

So, do I just stick with two pipes popping out of the roof, or combine everything into 1?

Thanks...Mike
 

John Gayewski

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This thread is getting old and too hard to look back on. You might want to post a diagram and ask your venting question. From the sound of it you may not be vented correctly.
 

Reach4

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Seems like a shame to get rid of a high-cost high-status durable slate roof.
 

hhcibtpaun

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This thread is getting old and too hard to look back on. You might want to post a diagram and ask your venting question. From the sound of it you may not be vented correctly.

Good point. I will try to get some pics to better detail. in words this is what I have (I will follow up with pics)

Vent 1: This is the original vent that vented everything (incorrectly I am sure). Now it will basically vent the toilet. If I keep it it will be a 3" pvc pipe off the top of the waste stack. Maybe 6' of pipe before it goes through the roof.

Vent 2: This is a 2" pipe that starts in the basement for the washer and laundry sink. It then comes through the kitchen and picks up the kitchen sink, then continues on to pick up the vent for the tub/shower and lav. The 2" will go into the attic, then I will upsize to 3" to go out the roof.

Seems like a shame to get rid of a high-cost high-status durable slate roof.''

Maybe. I think the roof is like 75-80 years old. If the home was some historic thing in a historic district I would try to keep it. It is impossible to find anyone to work on slate and if you do it is a fortune. I can get a new roof with all my vents cut in for $5500. I am thinking just to cut in the vents on a slate roof would be like $1000 if I am lucky. My roofer says his slate guy gets a few hundred dollars just to replace a few slates. He said the roof has seen better days :).

Thanks....Mike
 
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hhcibtpaun

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Vent 1: This is the original vent that vented everything (incorrectly I am sure). Now it will basically vent the toilet. If I keep it it will be a 3" pvc pipe off the top of the waste stack. Maybe 6' of pipe before it goes through the roof.

Vent 2: This is a 2" pipe that starts in the basement for the washer and laundry sink. It then comes through the kitchen and picks up the kitchen sink, then continues on to pick up the vent for the tub/shower and lav. The 2" will go into the attic, then I will upsize to 3" to go out the roof.

OK, I got some pictures to help with my descriptions. I will start in the basement and move up.

The BLUE is my main stack, that corresponds to Vent 1 in my description above. Starts in the basement, goes up through the kitchen, to the bathroom and out the roof.

The green is my new vent that will go up into the kitchen. Vent for laundry sink and washer.

full-basement-small.jpg


In the kitchen you can see Vent 1 just going straight up to the toilet.

stack-small.jpg


Vent 2. Is coming up a different wall and picks up the sink in the kitchen.

kitchen-small.jpg


Finally, we get to the second floor. I don't have the vent 1 pipe in yet, so I just colored where it would be. This currently goes through the roof.

bathroom stack-small.jpg


The next two pictures detail vent 2. The first one is the vent off the lav, that goes into a closet. Then the second is the closet that picks up the lav vent and the vent from the kitchen. This will then go through the attic and get upsized to 3" in the attic, then go through the roof.

bathroom-small.jpg
closet - small.jpg


For reference, here is what the bathroom plumbing looks like, with the green and blue highlighting general vent locations:

tub-lav-small.jpg


So, originally the plan was to have two vents poking out of the roof. Then I started thinking maybe I just poke Vent 2 out of the roof, and connect vent 1 to vent 2 in the attic. So, is it better to just have one come out of the roof, or should I stick with 2? I think I have like 15 DFUs. definitely less than 20 DFUs.

drawing-small.jpg


TIA...Mike
 

hhcibtpaun

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Folks,

In my quest to figure out what to do with my venting I found the following table in the IPC code:

ventTable.jpg


So, if I have a 3" stack vent and less than 21 fixture units, it calls out 110 feet of developed length for 2" vent pipe. Is that the sum of all my 2" vent pipe, or just the maximum length of any single vent section?

Also, if I am able to connect my vent stack (vent1 from previous post) to the other vent I added (vent 2) and just have one protrusion through the roof, can I size down the vent pipe to 2". where it would come up the wall in the bathroom? If I use the 3" I may have to pad the wall out a bit. I can do that, but if I am able to size down to 2", then take that 2" over to the 3" pipe it would be easier :).

Oh also, do I need to bring the pipe 2' out of the roof. I think I do, but I have seen 6" in some places. I think IPC is 2 feet.

Thanks...Mike
 

Reach4

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"The developed length of individual, branch, circuit, and relief vents shall be measured from
the farthest point of vent connection to the drainage system to the point of connection to
the vent stack, stack vent, or termination outside of the building." (page 4)

In very cold areas, the stack gets increased as it enters the non-heated space on its way up. This is to prevent the pipe from freezing closed in really cold weather. You are not in such a cold place. https://www.energystar.gov/ia/partners/bldrs_lenders_raters/downloads/County Level Design Temperature Reference Guide - 2015-06-24.pdf page "83" thru "85 shows 99% PA design temperatures for PA, and I think 99% is colder than the 97.5% number.


SECTION 903
VENT TERMINALS

903.1 Roof extension.
Open vent pipes that extend through a roof shall be terminated not less than [NUMBER] inches (mm) above the roof. Where a roof is to be used for assembly or as a promenade, observation deck, sunbathing deck or similar purposes, open vent pipes shall terminate not less than 7 feet (2134 mm) above the roof.

903.2 Frost closure.
Where the 97.5-percent value for outdoor design temperature is 0°F (-18°C) or less, vent extensions through a roof or wall shall be not less than 3 inches (76 mm) in diameter. Any increase in the size of the vent shall be made not less than 1 foot (305 mm) inside the thermal envelope of the building.


I don't see how the NUMBER, for how high the VTR must extend above the roof, gets determined, and I presume that is a local thing. Bethlehem says 12 inches.
 
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Jeff H Young

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There is no answer you connect the 2 pipes with one vent . or run seperate 2 vents out roof. Best is only one vent out roof . with no concideration for cost of labor or material. a single penetration is better how much better perhaps negligeable but its better. Ive never been to pennsylvania if it dosent snow id put vent 8 inches high if it does snow consult locals
 

hhcibtpaun

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. https://www.energystar.gov/ia/partners/bldrs_lenders_raters/downloads/County Level Design Temperature Reference Guide - 2015-06-24.pdf page "83" thru "85 shows 99% PA design temperatures for PA, and I think 99% is colder than the 97.5% number.
Thanks. Let me review the vent brochure.

I am in Bucks county, so the 1% cooling number is 89 and the 99% heating temperature is 16.

I think I found this and assumed it was IPC: Apparently it is the 2018 Philadelphia code?
https://up.codes/viewer/philadelphia/ipc-2018/chapter/9/vents#9 Maybe I will see if I can find the code for Doylestown,

Section 903 Vent Terminals

903.1 Roof Extension
Open vent pipes that extend through a roof shall be terminated not less than 24 inches (610 mm) above the roof. Where a roof is to be used for assembly or as a promenade, observation deck, sunbathing deck or similar purposes, open vent pipes shall terminate not less than 7 feet (2134 mm) above the roof.
 

hhcibtpaun

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There is no answer you connect the 2 pipes with one vent . or run seperate 2 vents out roof. Best is only one vent out roof . with no concideration for cost of labor or material. a single penetration is better how much better perhaps negligeable but its better. Ive never been to pennsylvania if it dosent snow id put vent 8 inches high if it does snow consult locals
Jeff,

Thanks. I will see if I can find the length in the local code. Maybe I will go with 1 vent out of the roof. I am doing the labor so it is free. Would be cheaper and easier if I run 2" pipe from the stack vent into the attic and connect to a 3" section that I send out teh roof? Is that acceptable from a code perspective. I think I read a WC could be vented with a 2" pipe, and that is basically what is being vented now that my new vent is picking up most other things...or do I stick with 3" and pad out my wall if need be?

Thanks...Mike
 
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Reach4

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Yes. Philadelphia code has some significant differences.

I would ask your county building code department on the required height. If there were no minimum, what height would you use then? Most of PA uses the unmodified 2018 IPC, but the unmodified 2018 IPC is silent on that.

Maybe look at other roofs, including new construction, and those might give you a good indication. If your vent is going to be on the side of the roof not visible from the street, then your concern about what it looks like should be less significant. Regular PVC should be protected against sun. Latex paint is one way. I might use 2 inch gray schedule 80 plastic conduit. I think it is treated for UV.

https://ecode360.com/32022076 says 12 inches for Township of Warrington, PA.

A roofer is the right person to finish this at the top.
 
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