rushing water noises in new home

hi
my new home plumbing is a disaster!!!
whenever we turn on shower faucet upstair, we can hear loud rushing noises in the downstair drainpipe, as it is raining over our head and the drainpipe behind our family room wall is the loudest as if we have a waterfall in the family room when someone upstair decides to take a bath and the noises coming down after the water is release from the upstair bathtub.
the builder has tried to improve this situation by making holes in the family room wall and put foams in trying to insulate the noise but did not help at all. my husband does not want anymore holes to be dug so what should we do??
the builder said if we want he can tear down the entire wall and see if repiping can be done but there is no gurantee that the rushing noises can disappear, and I just dont want to destroy a new home like that.
Another builder recommend to install water hammer device/pressure reducing valves to see if this noise can be improved by lowering the water pressure?
HELP !!! can anyone think of any other less invasive options???

If the noise is in the drain, then water hammer arrestors or pressure reducers on the supply line will not change that. It probably relates to the type of pipe used and how it was installed.

I think we would need to know more about the installation. One drastic measure is to install a sound wall. Frame a new wall of 2x4 on their side, not touching the old wall, and spaced about 2" out. Fill all the cavities with fibreglass, then put up a layer of 1/2 soundboard, and then 1/2" drywall.

This is drastic, and you will loose about 4" from the room size. I would not go there until all the facts were known, and even then only if the noise where such a huge issue for you that it is worth the effort.

Or, you could have the plastic pipes ripped out and Cast Iron pipes "the quiet pipe" installed. If it were me I'd do as Jimbo stated and learn to live with any balance of noise.

The plus sides of plastic pipe (PVC or ABS) drains they are cheap and will last forever without corroding. The down side is the water draining through them is quite noisy. Some of the noise can be lessened by insulation and isolation, but it is there to stay as long as you keep the plastic pipes. Water pressure and water hammer are conditions in a water supply not a drain, so there is no point in even considering either of those as possible sources of the noise. Most people find that in time they become accustomed to the sound, but it will still be there. Don't blame the builder or plumber for poor workmanship. Cast iron would be the only real solution, but it would be very costly at this point as there would be much demolition and rebuilding to be done as well as the cost of the CI and installation.

That is how 99% percent of new homes are built.

Only the smallest percentage of homes get cast iron drains.
I saw some new cast iron drains the other day, while I was installing a $3700 Neorest 600 toilet. The think the house and land was valued in the tens of millions.

I have no idea why the pipes are so noisy. I have a second-story bathroom and when the Gerber Power Flush kicks in, you can hear it, but you can't hear running water otherwise. I have no insulation. The pipes running all the way across the livingroom ceiling are ABS plastic. I can't help but wonder if there's some other factor contributing to the noise.

I saw some new cast iron drains the other day, while I was installing a $3700 Neorest 600 toilet. The think the house and land was valued in the tens of millions.

Click to expand...

My 1950s rambler has cast iron drains. Beautiful, quiet, cast iron pipes. For today, and today only Terry, I would be willing to sell it for a million.

Any takers?

I am cutting my own throat here.

Now, which wise guy is going to mention "different animal" and "sand cast"?