We are remodeling the bathroom, moving the sink and bathtub (originally a shower). The shower and toilet were along the same pipe line and vented in a privacy wall next to the toilet. The sink used and AAV. I can continue to use AAV in the new sink location or tie all three into the same vent (if possible). All three walls that could be used for venting are structural walls and cannot be used for venting (as far as I know). The one internal wall has a triple joist beneath it so cannot be accessed directly. Based on my image showing the placement of the sink, bathtub and toilet, along with the existing plumbing locations, what are my options for venting? Am I able to vent with just one vent? Will I need two separate vents? What locations are available to me that don't require the privacy wall? I figured the shower would have to be vented in the adjacent wall by the drain, but I'm unsure about the sink and toilet. If I doubled the thickness of the wall behind the toilet (added another 2x4 wall) I could vent in that "false wall", but it would visually look odd having just that section twice as thick as the section on the other side of the door. Any options and advice are welcome! Thanks! [url=https://drive.google.com/uc?export=view&id=1-s6G9eTu-rNU6UrgXmT0ttg9pOssgqGf][/url] [b]CLICK THE PICTURE TO SEE MORE DETAIL[/b]

Ever since we bought our current house, there has been a drip sound in the wall when the bathroom sink is draining. It also happens sometimes when the washing machine is draining with is located in a laundry closet on same floor kind of adjacent to the bathroom. So they share a common drain route heading to the basement and out of the house. I have gone as far as cutting large pieces of drywall out looking for a leak. And have never found a leak, water stains or water damage. I can put my ear right up to where the drip sound is and there is nothing. It sounds like maybe it is echoing up through the pipe maybe. Have any of you ever heard of something like this and it being a drip inside the drain pipe? Maybe dripping from drain tee or something. What do you think?