Flushing noises Home › Forums › Public Forums › General Plumbing › Flushing noises This topic has 1 reply, 2 voices, and was last updated 23 years, 6 months ago by fourth year. Viewing 1 reply thread Author Posts 14 Jul 2001 at 10:50 am #275074 PACIFIC CREST PLUMBING Is there any way to eliminate the cascading waterfall sound that runs down a two story great room wall when the upstairs commode is flushed? 14 Jul 2001 at 8:47 pm #291034 fourth yearParticipant No easy way. Replacing the plastic drain line with cast-iron will help considerably. Insulating the wall cavity will also reduce the sound. Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In