Kitchen sink u-bend block puzzle

Spudtm

Have recently had house refurbished from top to bottom, including new kitchen, ceiling removed, walls plastered, new tiles - everything. Kitchen completely re-plumbed. Used kitchen sink for a week, and leak developed around u-bend.  Called plumber (not one who did kitchen) and he found rubble in u-bend, and in waste pipe. Outside drain also blocked. How would rubble have got there? Thank you

neilmcl

When was the kitchen sink plumbed in in relation to the other jobs in the kitchen? Sounds like your workmen decided to pour/clean out their plaster buckets down the plughole.

grumbler

Spudtm said:

 leak developed around u-bend.  Called plumber (not one who did kitchen) and he found rubble in u-bend, and in waste pipe.

Rubble is bad and needs removing, but it shouldn't cause leak.