Toilet/Bathroom piping?

Question

I was wondering, when I flush, turn on a tap, etc and someone is showering... the water becomes cold or hot depending which tap I turn on, I was wondering if there a way to make the water not change temperatures if someone flushes, or is it because of the piping of the house?

Answer 1

Domestic water system is 15mm piping so your water pressure is uniform throughout the property.

Some systems run partly of a header tank and some directly from the mains.

From the sounds of it your system runs from the mains with no header tank. Therefore when you turn on more then one tap in the house or flush the WC and turn on a tap the water pressure is divided between these. Hence pressure reduces in the shower or other area, the mix of hot and cold water is interrupted.

It is possible to get over this problem by installing a header tank, (as this is classed as still water it is not recommended for drinking) A header tank is a water storage tank, normally located in the loft or airing cupboard higher then the appliance as it is gravity fed. It can be used for flushing WC or connecting to a shower, although just like the WC it will start to fill as soon as you flush so I would recommend connecting it to your shower. this will resolve your problem.

Now do you have room for the header tank in your loft, I would recommend you get a plumber to suggest where one could go. But get one with credentials as someone with DIY experience could mess this up for you.

Answer 2

Nope, thats just the way plumbing is, so dont flush when someone is taking a shower

Answer 3

save yourself a lot of trouble, install pressure balanced taps in your shower and live with the rest, unless you want to spend alot of money

Answer 4

nothing you can do unless you change how your home is piped out

Answer 5

its the pipe size and water pressure. maybe old pipes / clogging.

Answer 6

ty808 id probably 99% correct - old or under-sized water piping.  But there is a small chance (one that should be investigated) that a valve is not open all the way, or that there is a defective PRV (pressure reducing valve) in-line somewhere.  Or that the water supplier is not providing adequate water pressure.

All are pretty easy to look at.  It might be a good idea to call a plumber, who could probably spot the cause right off.