Plumbing Questions? Ask a Plumbing Expert.
If the toilet bubble ups when you're taking a shower there isn't anything wrong with the toilet. It sounds like the drain is partially clogged up. It could be a vent problem, but I think if you snake the drain downstream of the toilet you should solve the problem. If there is no clean-out on the waste line, you may have to remove the toilet to snake out the line. You could also try the drain king This attachés to a hose and you put it in the drain and turn the water on. i would try short blasts especially if you are on an upper floor on the house. You want to be careful not to have the water back up and through the ceiling. Have a wet vacuum and rags ready. Or rent an electric snake for a 3" waste line and try to snake out the line. Good Luck Plumbertom
Is this a one story home? Tom
I would check the septic tank and the line running out to it. It may take water from a hose, but it's possible that it is backing up and closing off the vents connected to the sewer. There may be a problem with the fixture vents but I find that is a rare occurrence. Tom
I've never seen a toilet bubble up and had something wrong with the toilet. The fact that it doesn't work when you are taking a shower tells me it has to be a problem with the waste line. If the master toilet is the closest fixture to where the sewer leaves the house then I think the line is backing up and blocking the vent line. That is the only answer I can come up with besides a clogged vent line above the toilet which would be rare. With the information you have given me, this is what I think is wrong. Tom