Bathroom sink leak and come through my kitchen ceiling. Can a blocked vent on the roof be the basis? The bathroom since had be blocked and over a period of days...

The bathroom since had be blocked and over a period of days I added every chemical I could, plunged, and snaked it but it would not unclog. Then when it did it leak into my kitchen ceiling underneath. I have not fixed it however because I thought it would cost a lot and possibly call for to rip up part of the floor to find/fix the problem. The tub and toilet work fine, run for a time slow most of the time but cause no leak. Now I have be told that it may be pigeons that nest on my roof eve due to a overhang since the house next door is so close that own blocked the vent. Can it be the vent and who would I call? Plumber, roofer, extermintor? They enjoy been here since I bought the home 5 yrs ago and it be empty 2 previously that so they aren't going to leave confidently! I don't have deeply of money and don't know what to do first. Any suggestions?
Answers:    Some very "interesting" conditions here. When you utter the vent is clogged, what do you mean? Usually a stack vent is vertically mounted from the roof. Have the pidgeons if truth be told built nesting over or in the vent? In any case, this should be an straightforward fix. Get on the roof, clean out the nouns on, around or in the vent pipe and later measure the outer diameter of the pipe itself. Go to Loews or Home Depot and take a pipe cap. It is a small round sou`wester that has vent on it and simply screws onto the top of the vent pipe. That will stop any further blockage. ( Pipe cap runs about $12 contained by galvanized tin). If your tub and toilet are working fine, afterwards the vent is NOT the basic problem though. If your vent were completely clogged, it would affect adjectives the lines connected to it, which include the tub and toilet. At this point, personally, I would disconnect and remove the P trap beneath the sink and try running a snake direct into the line. Naturally, check your P trap and kind sure it is unobstructed. If your snake will not reach the clog, it might be time to telephone in a professional plumber. As far as the ceiling bleed down into the kitchen area, first embezzle care of the bathroom sink. I dont know how fruitless the ceiling leaked on you, but unwanted moisture is NEVER flawless. If this was a fundamentally small stain on drywall, personally I would remove a small patch, adjectives completely around the wet nouns to assess the damage, use an electric admirer to dry out the area. If no further smash up was done, when the trickle is fixed and the area is dry, use some 1x4" slats over the top of the hole you cut out, screw them from your side of the ceiling. That gives you protection. Now cut out a piece of sheetrock to fit the hole and use drywall screws into the 1x4" slats. Tape, mud and sand the nouns. Use KILZ II primer. It seals the nouns and helps prevent mold and mildew. Then paint. I know this sounds close to a lot, but cart it all a step at a time. I hope this help you.
When you plunged you probably separated the pipes under the sink try tightening adjectives of them may need to grasp some plumbers tape to reinforce them. Far as the mess depends what be the clog hair maybe no problem but the chemicals you poured down probably lye should not be a problem either only fix the ceiling. May need to a short time ago patch may need someone to sheetrock and cassette and bed prime it and paint it and yes probably the whole ceiling. Hard to stop fine art if paint is 5 years old! I dont reckon anything on roof could possible have anything to do beside it. Oh yeah before you tighten up be sure to verbs the pipes out if clog is still there graceful! Good Luck!