Why do my pipes rattle and hum after I flush my toilet?

Answer by  TheRealPlumber (249)

This could be cuased by a loose pipe in the wall or by air in you piping system. You will have to determine the cause and location of the rattle.

Answer by  worker4855 (20)

Your water supply pipes were probably not secured properly during installation and have come loose if the installers even bothered to secure them. The water flowing through the pipes causes them to flail about and beat against whatever surfaces they come in contact with. The resulting noises are professionally known as "water hammer".

Answer by  ujwalraimjoshi (729)

Call plumber. Check the outlet connection of flush, washer. Blocked air or imbalance of water pressure may be causes of rattle and hum.