Plumbing Vents on My Roof

[Daavewaard]

I am often surprised when I notice residences and apartments with vents everywhere and with several placed haphazardly in a relatively small space on the roof. One of these days I'll be building my dream home and one objective will be to reduce the number of holes in my roof and another will be to place vents in the most inconspicuous places as possible.

So, my questions deal with the notion of bringing two or more vent pipes together in the attic and combining them so there is only one vent through the roof. Can I assume that it's OK to have horizontal runs of vent pipe in the attic? Can I combine multiple vents into one? Can I vent elsewhere than the roof proper, like behind an attic vent at a peak? Thanks!!

 

[hj]

You can do anything you are willing to pay for, because while it can be done, it is not "free".

 

[Sponsor]

 

[Reach4]

To help keep a clean looking roof, I suggest you search the web for the following: attic "conditioned space"

Regarding where and how high plumbing vent penetrations must be, that is largely local. But you can run "horizontal" in the attic, but it must have a slight slope for rain.

 

[Edwardh1]

beware, my sons 3500 ft2 late 90s mcmansion had only one or 2 vents and on the back. after finding gurgling in some of the bathrooms we located the horizontal attic vent pipes that had sags in them and the sags had water in them we guess from heavy rain, inadequate pie supports

 

[hj]

If they had that much water in them then it was a VERY incompetent plumber who installed them.