I think you've received sufficient answers, but I wanted to reinforce what
others have stated. It isn't the pressure, its the shower head. I switched
my shower head to a low pressure model and right away I noticed a huge
difference in how the show "felt". It took some experimenting to be sure,
but I wouldn't trade my current one for nothing - and I've had it for years
now. Going to 3/4" is just going to make you hate life - especially
considering that you'll have to neck it down to 1/2" anyways at the shower
head - so all that 3/4" inch pipe won't make any difference anyway.
Not to be argumentative with other posters, but 3/4 pipe has less
resistance to flow than 1/2, so for a given flow rate and pipe length
there *will* be less pressure drop, resulting in higher pressure
available at the shower head. But unless you have a very long run
it's won't be enough difference to make it worthwhile. BTW, this is
true even if your valve is 1/2, but the flow resistance of the valve
may very well cancel out the gain from upping the pipe size.
Others have made good suggestions, let me add another point: If your
showers are on higher floors, you loose a lot a pressure overcoming
gravity. This exacerbates the problem, especially if your pressure is
marginal to begin with.
A more practical solution than re-piping may be to add a booster pump.
If your main supply pressure is truly marginal, a booster pump will
work wonders. They are available as packaged solutions with a pump,
controls, and a very small pressure tank. Placed inline with your
cold water supply, it will help both cold and hot pressure throughout
Yes, this is what I'm thinking could be the case. But I would like to
find out for more certain.
This shower's on the lower floor.
Yes I've thought of this. But I'm not comfortable with the idea of
increasing the pressure for the entire household. If one of my
neighbors learned I was doing this during the summer months when water
restrictions are in effect (and inexplicably, water pressure for
everybody in the neighborhood always seems to be much lower than during
the rest of the year), I'm pretty sure I'd soon receive a visitor from
the city abruptly ordering me to 'shut er down' due to some
bureaucratic bylaw prohibiting such. (Hey, in this city where I now
live it's even illegal to use a sump pump, because -silly as it may
seem- that is considered to be abuse of public sewer system capacity.)
"My shower lacks pressure so I want to replace the existing 1/2 inch
pipe that leads up to it with 3/4 inch copper pipe. Obviously, if done
correctly this will increase the water pressure available at my
The first paragraph of your post is incorrect and untrue. It makes me
wonder how you could be so judgemental of everyone's response when you
don't have a clue of what your asking yourself.
Measure the pressure available - if it is low, that is your problem.
If not, raising the heater temp may help because then more cold
would be added to it to get the right temp - reducing pressure
losses in the hot pipe.
Did you have the problem before installing the balsance valve?
I noticed everyone and his mother has been giving you advice. This
is coming from the plumbing newsgroup.
Increasing the feed pipes to 3/4" won't help. Incidentally, since
water is not compressible, the smallest pipe or port in the system
affects whatever's after it.
Here's three thoughts..
#1 Is the shower the only place in your house where this low
pressure occurs? If this problem exists elsewhere, write back for more
#2 Since the problem isn't a clogged shower head (which was the
first thing to check), then, assuming some rust hasn't lodged in the
valve body, I'd suspect the balancing valve itself. If you're handy
enough, take the valve out and see if that doesn't increase the
pressure. If it does, then just get a new valve. BTW, you shouldn't
need a balancing valve. Something is awry somewhere. Perhaps you'll
end up repiping the main arteries that feed the fixtures.
#3 Don't ask plumbing questions in the "alt.home.repair" group,
unless you want a bunch of amateurish, faulty advice.
First do what I've suggested, then write the plumbing group if you
need more advice. Sice we're not there to look at things ourselves, it
might take a message or two.
Thanks. Finally a response suggesting credibility.
Okay, this appears on the surface to be saying exactly what others
before you have been saying. Am I to be sure then that you mean to be
saying here that using 3/4" pipe in place of the current 1/2" pipe
*won't* result in less pressure loss (in relation to the main supply
line into the house)? If so, maybe you could indulge my curiosity and
explain how this can be so in light of the many references that appear
to say otherwise (such as the "Bob Villa" reference I quoted, for
example)? But somehow I'm inclined to to think you don't mean to be
saying this at all, but rather could be somewhat misunderstanding my
Thank you!. So a reduction in pipe diameter from, say 3/4" to 1/2" for
a travel distance of, say, 4" (the length of my PB valve) and then back
again, would definitely limit the pressure at the end to what it would
be if the entire line were just 1/2" in diameter to begin with?
No, the pressure is low throughout the house. (Bear in mind, however,
that when I say "low", I don't mean abnormally low; just lower than
what I've been used to from older dwellings I've lived in prior. I can
write back later and give you the actual psi value since my memory is
not so numerically precise, but I will tell you now that I recall
checking the water pressure at an outside faucet in the past and
finding it to be within the lower end of the normal range.)
Okay, I don't have the valve installed yet. When I bought this house
there were no pressure balance valves installed whatsoever. Since the
time it was built however, local laws have come into effect that
require these be installed for each shower in all new (as well as legal
rental) dwellings. I have bought an inline pressure-balance valve
still waiting for me to install. But it's openings are only standard
1/2", as opposed to the 3/4" piping I have more recently been thinking
of installing for a separate and totally distinct reason (i.e. my
personal preference for increased overall pressure to shower - think
'President Lyndon Johnson with his 100 PSI shower in the White
House...', though not necessarily that extreme <g>)..., thus prompting
my original question.
This comes to me as a surprise. In every house I've ever lived in
prior to, as well as including, this one, people have had to time their
showers (or tell others before showering) in order to avoid being
scalded or cold-shocked while showering. I remember my Dad turning
down the thermostat of a new hot water tank that had just been
installed in his house, as a safety precaution to decrease the chance
of somebody getting seriously injured while showering in the event that
somebody opened or closed a tap somewhere unawares during.
Pressure and volume are different things. Increasing the pipe size will NOT
increase the pressure. Can't happen. Won't happen. Put in a 6" pipe and
you won't get any more pressure If your feed from the street is corroded,
you may get better flow by replacing it, but putting in a section of larger
pipe will do nothing.
If you want to increase the pressure, the first step is to find what
pressure is at the street. Then you compare that to your house. If they
are the same, nothing you do will increase it. If you get a big pressure
drop, it may be from a flow restriction on the main to the house. What size
and type of pipe is it? If it is an old galvanzied pipe it may be corroded
or have buildup inside and giving restriction. This is a different scenario
than what you are suggesting. Replacing a section inside will do nothing.
If you want a high pressure shower, move to the town that I work in. We
have 110 psi feed.
In the original post increasing the size won't do anything measurable,
"Can't happen. Won't happen" I don't think so.
In theory and in practice with long runs pressure drops will add up
and increasing the pipe diameter will increase the pressure at the
Increasing pipe diameter reduces restriction on the flow. Static pressure
remains exactly the same. There will be less pressure drop once the flow is
started. But pressure is never increased by larger pipes.
Which is the condition when actually using your plumbing.
The above is totally misleading. The only pressure that is relevant to
the OP is during flow, so that if you wanted to stay relevant then you
should of said.
"The pressure can be increased by larger pipes"
No, it can not. Restrictions are removed, but pressure is not increased,
just decreased less.
Think about that for a minute and once you know the difference, you can cure
the problems easier. Along the same lines, can you make something colder?
No. You can, however, remove heat. The physical differences is of the
utmost importance when dealing with changing pressures or temperatures.
Unless you know what characteristics are the ones affecting your situation,
it is a crap shoot to find a cure.
Bigger pipes do not make more pressure. This is not my opinion, this is the
laws of physics. I didn't write them, but we all must abide by them.
Oh my! You came here knowing nothing and now you disparage comments by
others. Just what is misrepresented?
No one has yet explained or proven that a larger pipe will INCREASE
pressure. The only way to increase pressure is to have a higher head or
mechanically, as with a pump. There are ways of reducing pressure drop, but
that is a different method all together.
Did you understand my analogy of making cold?
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.