I am building a new bathroom in our church. The toilet will sit on a concrete basement floor so I will be cutting out the floor to install the drain. I can't run the vent up the wall in back of the toilet because there is a stone wall. So, I would like to vent it up a side wall. How close does the vent have to be to the toilet?






H

Vent take off needs to be within six feet of closet bend. As long as your vent is taken off within six feet, you can run pretty much as far as you need.

If local codes permit why not connect the lavatorydrain to the toilet drain and let it be wet vented by the lavatory toof vent. A bonus is that if you wish to add a shower all you have to do is connect it to the lavatory drain and it will be wetvented as well. So all you will have to do is run one vent, ( if t there's a dry vent handy to revent back to that would be nice)

Tom gave you a good option. If you go this route, make sure the lav drain and vent are minimum two inch all the way up to the roof, as toilet vents require a two inch vent min.

Now, why didn't I think of that? Thanks. I have done a lot of work on my house over the last 30 years... and learned by my mistakes! I need to engineer this project so that it is right - the first time. If I install a Wet Vent system from the sink to vent the toilet, I assume the pipe should be oversized to accommodate the duel function??

Correct. And two inch is oversized for the sink drain and vent, but large enough for the toilet vent. So two inch sink drain(acting as the toilet vent) is just fine, as long as you carry the two inch sink vent all the way up.