What makes my water pressure low when someone flushes a toilet or turns on water? Can it be fixed?

Question

If I am taking a shower and someone else is using water any where in the house the water pressure drops drastically. My neighbors do not have the same problem.

Answer 1

There are pressure balancing valves for showers that may be useful to you:

e.g.: http://www.powerscontrols.com/pdf/B-470....

http://www.groheamerica.com/t/_4706.html

http://www.moen.com/browsecatalog/produc...

Answer 2

Your water pressure drops because your supply lines are either clogged up with tuberculation (for more info about tuberculation, check out this page: http://www.curaflo.com/CuraFlo/AboutPipe... ) or are undersized. Only so much water is in your supply lines at any time, and that gets divided up by the number of fixtures you have. So for example, if you only have the showing running, all the pressure and flow is in one direction. But if someone then opens a faucet, your water supply and its pressure are now divided. I'd first recommend trying to increase your pressure by adjusting your PRV (pressure reducing valve), but if that doesn't work I'd recommend epoxy lining or repipe (replacing your pipe).

Answer 3

Check the main shut off valve to be sure it is fully on.

Answer 4

this is a very common problem

water comes into your house on one line, the main line, from there it branches off into different rooms and eventually different parts of different rooms

there is only so much pressure on the mainline coming from the water man that runs on the street, this pressure is build by gravity using water towers however if you live on top of a hill, then the pressure decreases because the water has to run uphill to get to your house

this pressure is what pushes the water throughout your house and out the faucets and into the toilet

when you open the valve on the shower the pressure on all the lines goes down drastically, however when you add the decrease in pressure from flushing the toilet or opening another sink to get water there will be almost no pressure at all in the line, causing the water to come out slower

unfortunately there is no easy fix for this prolem

Answer 5

Yes, a pressure balancing valve helps with this problem, but it isn't a user friendly item.  You have to open up walls, and usually the pipes are old and don't want to cooperate. The problem is usually traced back to pipes that are undersized.