Replies

1. 
   Jim_Lovatt | Oct 11, 2000 05:14pm | #1

   *
   Hi Maure. I would run a 2 inch vent from your vanity through the roof and a 2 inch drain from your vanity that enters your 3 inch waste pipe just after it goes horizontal. Then I would add a 2 inch vent from your toilet that connects to your vanity vent at least a foot above the sink. Code probably allows 1 1/2" pipe for this but I would use 2".

1. 
   Mr._Pita | Oct 11, 2000 05:30pm | #2

   *I don't know about the sizing of the vent pipe or if the toilet needs seperate venting. What concerns me is you mention a rise (fall) of only 4 inches. It sounds like the overall run is 23', which dictates a fall of 5.75". You generally need .25" fall per foot run of pipe.I made a quick sketch of what I visualize you want to do. The height difference between A and B needs to be 5.75" - do you have this much space to work with?

1. 
   Jim_Lovatt | Oct 11, 2000 06:48pm | #3

   *Mr Pita, inspectors I have encountered say you must slope 1/8" to 1/4" per foot. I think his slope should be fine. I believe your sketch creates a "wet vent", meaning the toilet vent is also a drain line for the sink, which is not allowed in certain situations.but then again i could be wrong ;-)

1. 
   Mr._Pita | Oct 11, 2000 07:24pm | #4

   *Yes, as you say it's a wet vent. That's what I thought he wanted. May or may not be acceptable, as you say. I kinda knew (I read somewhere) the shallower slope was OK, I just had 1/4 drilled into me so hard I ignore the alternatives. Just a personal quirk.In any event, Mauri, any advice from here should be run by your local inspector as he/she may not like it.

1. 
   David_Thomas | Oct 11, 2000 08:46pm | #5

   *1/8" per foot (2.875" over 23') is usually acceptable although 1/4" is better. 4" sounds fine to me. Wet vents are not allowed in all jusrisdictions and 5 feet would be at the limit if they are. I was allowed a wet vent for a sink, but not for the toilet. My code requires 2" vent on a toilet, even though the number of fixture units suggest 1-1/2" would be okay, toilets are an exception and need a 2" vent.Your mileage may differ. Objects in mirror are closer than they appear. Talk to your inspector before committing. -David

2. 
   Mr._Pita | Oct 11, 2000 09:32pm | #6

   *I like that signature. Might have to copy it...

3. 
   mauri_meere | Oct 11, 2000 10:11pm | #7

   *The inspector does like to send time answering questions, he wants to inspect the work after it has been done.

4. 
   Jim_Lovatt | Oct 12, 2000 12:11am | #8

   *I think we can all agree that for this type of venting we don't want to dense-pack it with cellulose.;-)

5. 
   Ralph_Wicklund | Oct 12, 2000 02:18am | #9

   *You've got to have the right sized pipe or it will dense pack itself.

6. 
   Frank_DuVal | Oct 12, 2000 03:41am | #10

   *Yes, the toilet needs a 2" vent line.Check out a Taunton publication by Peter ____ on Plumbing a House. It shows several different ways to roll a 3x3x2 wye or tee to get the 2" vent line into the 3" waste line and still have the vent going towards the vanity area where you can 90 elbow it vertical and join it with the vanity vent and then up through the roof. Vanity vent can be 1 1/2" from the vanity sanitary tee to the toilet vent line.According to CABO, a 1 1/2" wet vent from the toilet to the vanity is OK. See code section 3601.7.1. No maximun length of run from toilet to vanity is listed. The 2" requirement must be from some other plumbing code. Again, check your local requirements....Frank DuVal

7. 
   Coolflow_ | Oct 12, 2000 06:18am | #11

   *Mauri:Rex Cauldwell wrote a very good piece on venting in the May or June 1999 Journal of Light Construction. I also recall something in FHB but can't remember the issue-sorry.The book Frank mentions is by Peter Hemp and should be available at larger book stores.If all else fails you could try asking here.

8. 
   Jerry_G. | Oct 13, 2000 11:39am | #12

   *The 2 inch pipe for venting sounds like the way to go.You didnt say where you'r from, but in my area of(Mich)they are requiring us to convert from the 2 inch to 3 inch as you go through the roof as to avoid a possible plugging of the vent stack from frost in cold temperatures.

9. 
   Andy_Engel_ | Oct 13, 2000 09:05pm | #13

   *Not to plug our own books, but I think Peter's book on plumbing and Rex's books on wiring a house are two of the best on the topics anywhere. I plumbed and wired my own house based largely on experience, but I had both of those books at hand for those spots when experience failed (After all, I was mainly a carpenter). If anything, these two guys showed me how to do the jobs better than I'd learned in 15 years of working with and watching my local pros.Andy

10. 
    mauri_meere | Oct 13, 2000 11:38pm | #14

    *A few messages back, I meant to write the inspector 'does not'like to give advice, I wrote mistakenly that he 'does'.I cannot find Hemp's book in Ottawa.Andy, can you recall the article in FHB that I refer to in my original message.

11. 
    David_Thomas | Oct 14, 2000 01:40am | #15

    *Andy: I gotta add my thoughts on four Taunton books. I agree that Hemp's two books on plumbing are stellar. I've given a bunch to owner-builders. Taunton's tiling book is another excellent one. Cauldwell's wiring is good. I haven't seen better, (I haven't looked much), but it is not of the same very high caliber as the plumbing and tiling books. -David

12. 
    mauri_meere | Oct 14, 2000 05:35am | #16

    *If I understand the responses correctly, the answer to my original question is that either method of venting should pass inspection.

2. 
   mauri_meere | Oct 14, 2000 05:35am | #17

   *
   I need some advice on venting.Some time ago FHB carried an artile on venting, it was plumbing code in lay language...but I am having problems finding it. Can anyone help? In the mean time here is my situation,
   I enlarged my one story addition to include a mudroom.The addition is attached to my two story home. Now I want to build a half bath(just a toilet and vanity) in the mudroom. The toilet will be located about 18 feet from the main stack in the original structure. I can run a 3 inch waste in the basement under the joists and tap into the main stack.I can probably get a rise of 4 inches over the 18 feet without too much problem. The vanity will be placed about 5 feet beyond the toilet. I will extend the new 3 inch waste pipe the extra 5 feet to the vanity and tap into it with a 2 inch pipe. There is no easy way to vent back to the main stack so I will vent through the addition roof. Can I vent just the vanity after the trap and through the roof? Or do I need to create a vent from the new 3 inch waste just after the toilet and connect the vanity vent to it in the attic space and then through the roof? And what size pipes should I be using? I am dealing with very little space and looking for the simplest solution to my problem. Thanks for any suggestions.