I have recently installed a new dishwasher and sink (approx. 6 months ago), within the past week my kithcen sink will not drain. Went on roof with snake and at approx. 15 ft. had a clog could not break through. Any suggestions?

You can remove the "J" bend from the trap and snake the drain line, (see image). You will run into a 90 degree bend about 8 inches in but once around that you only have to put out 6 more feet of cable. After, flush with hot water.

John

If your sure that the clog's in the roof vent then rent a Rigid K-60 sewer machine and try again,