I've snake both tubs, and cut open tub drain between the trap and main line, no blockage. There no bubbling noise while draing. I'm goning on the roof and snake out the vent lines
My neighbor has a split level that the h.ba and m.ba are draining slowly, no bubbling noises as they drain which would suggest some type of vent blockage or blockage. There was a 1/2 ba. added down stair main floor 2 years ago, but everything else is draining great. I'm going on roof and snake the the vents next.The new 1/2 ba. has a 1-1/2 vent. Any suggestion?
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Now from what I understand is that there are two baths upstairs that are not draining properly. Both slow. Are they both back to back? or close to each other. Meaning are they both sharing ...»
My 2nd question would be, is the toilets or sinks in those two baths having any issues such as slow draining?
Reason I ask these questions is to rule out parts of the drain system so to isolate where you need to be looking.
According to your knowledge the sinks are ok. This makes me think that any blockage is before the sink connection to the drain line but after the tubs. So your looking at a common drain line in which the tubs/showers are connected prior to the sinks or toilets in the home.
Although I doubt the issue is the vent system. While it could be the reason, but if the trap was really the issue you would hear all sorts of noise out of the other adjoining tub fixture as air was trying to enter through its trap. If you did hear noise then I would suspect the roof vent after both tubs connection point to be plugged.
So my guess is that what ever is plugging the drain is right after the tub connections point but prior to the connection point of the sinks.
So that is where you want to be sure to snake to. If you can snake from the tub connection(s) down stream to at least past the sink point in which they connect. I would think you would have found your issue. This may save you going on the roof which is not a pretty job when using a snake system. Not safe and not very easy.