Water Pressure

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Posted by: from Georgetown
1/3/2013 at 9:00:06 PM

The water pressure in every bathroom in my house is excellent except for one. The Shower in the master bedroom has extremely low water pressure. I've even tried switching the shower heads because the one in the master shower was beginning to show signs of corrosion.

Any ideas why my one bathroom has lower water pressure?

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Bobby from Construction A-Z in Laval
Date/Time1/3/2013 at 10:09:13 PM


Replace the cartige inside your faucet. Is doable from the front. If not you need to replace your faucet.

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Date/Time1/3/2013 at 10:56:13 PM

My suggestion would be to check the mixing valve. This is behind the knob you use to turn the water on and off and change the temperature in the shower. First you have to turn off the main water shut off to the house and open several faucets in the house to let the residual water in the lines drain down the sink.

It's alway good to open the faucets in the basement as well if you have any. Then in most cases there's a small plastic cover that can be removed with a thin flathead screwdriver or utility knife and underneath there is a screw that allowed you to remove the handle.

In some cases there is a set screw under the bottom side of the handle that once it's loosened you can remove the handle and expose the mixing valve. After you do this you will most likely see a couple screws that aloe you to take off the face plate, undo them and take the face plate off.

Now the mixing valve will be exposed.

Depending on the make of the faucet there maybe a retaining clip that will have to be removed, some are internal rings that have to be squeezed together with a set of retaining ring pliers ($10.00 at most hardware store) or some may have to be spread open to get them out.

After that you can use a socket, adjustable or a set of channel locks to unscrew the cartridge. Take the cartridge to a local plumbing supply store and they will most likely replace it for free depending on the make of the faucet. Take it home and work backwards through the steps I just explained to you to put everything back together.

This would be my first trouble shooting method as sometimes the heat from soldering the pipes during plumbing rough in durning the home build damage the seals in the cartridge and melt into the path of water flow in the valve.

Most likely this should fix your problem.... Let me know how you make out!

Kind regards

Brandon Hottot

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Date/Time1/3/2013 at 11:34:57 PM

Hello Nolan, If you have good pressure to the rest of your house-you will need to replace the cartridge inside your faucet- The comment by Brandon Hottot is a perfect explanation of how this is done.

Good Luck.

Bruce Tiffiin

Granite Wood Construction

Georgian Bay, Parry Sound, Muskoka

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Design Worx Kitchen, Bath, Painting and Antiques in Barrie
Date/Time1/3/2013 at 11:37:08 PM

I have many situations with water pressure being a problem in a client's house during a renovation of the kitchen or bathroom. I have found through trial and error that it could be the city's water pressure changed, and it even happened in my own house. The city of Barrie changed the water treatment plant and the water pressure to the house changed. My house is 16 years old and after 12 years here with great pressure to both sides of the outside house garden hoses, one of the hoses could not hold pressure when you had both sprinklers on at the same time. I had my plumber come and have a look at the problem and he said it was the city's issue not mine. The city has since put a water tower on our street to correct the problem.

On another job also in Barrie, we had to put a pump on the main water supply to the house as the water pressure was again to low and the plumbers could not correct the problem as it was a city issue. The pump cost the client $1200 to install and they have not in 5 years had any more complaints since.

The only other thing that I have found is roots in the main pipes slowing down the water flow to the main house. The pipes were dug up in the front yard, fixed and water pressure restored.

I hope that this information is helpful, and have a great day.

Melissa-Jean Daunt

Design Worx


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R. from R2 Renovations in Ottawa
Date/Time1/4/2013 at 8:46:26 AM


My guess is that you need to check or replace your mixing valve. You can attempt this yourself or hire a plumber. Plumbers in my area charge 60 - 80 hr. May be worth it for you to bite the bullet and hire one.

You may also have a pex line running from your valve to the shower head. It has a smaller interior diameter then copper. decreasing the flow a little. But if is "extreemly low " I would check the valve.


R2 Renos

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Date/Time1/4/2013 at 10:57:15 AM

Hi There

It could be many things. For starters your psi at the main valve may not be up high enough and although the pressure may be good up to that point as it may be the farthest pipe run. It could be a build up of hard water in an elbow feeding your shower valve or it could be a build up in the valve itself not allowing sufficient water to pass.

We can do an investigation for you first hour is free second hour is $65/hr and each thereafter. This would only be for diagnostics. A written report would be $175.00 this you could then hire anyone to repair it or we can give you an estimate for repair not requiring you purchase the report. Hope this helps.

Andrew @ trades4theday

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Dolphin Construction Co. in Ottawa
Date/Time1/4/2013 at 1:16:07 PM

Change your mixing valve You have to remove it anyway to check your water pressure up to this point. If you changed your shower head you can do that too.

Good luck.

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Date/Time1/4/2013 at 7:09:41 PM

Switch off the main water valve for entire house. Take apart your shower controls, to find any lime scale pieces. Sometime any object can block piping.

Good luck.

JMB Canpol Builders Ltd.

Jozef Blaszczak


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Date/Time1/4/2013 at 8:33:25 PM

The most likely cause is the shower faucet itself. Either it has corrosion or debris logged inside the mixing valve.

Georgetown I believe is still on well water for most of the city, which causes a lot of problems due to the mineral content in the water. Or it's just worn out. Either way for the cost of a new valve ($20-50) it's just best to replace it.

If the problem has been there since you moved in and you have plastic water pipes. One of the pipes might have been kinked when it was installed, which would cause your low pressure/flow.

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