What causes low water pressure in your house?

Low water pressure is a frequent problem in many houses. There are multiple things that can cause low water pressure in your home. An experienced plumber knows exactly what to look for and how to treat the problem most efficiently.

The first thing that St Paul Pipeworks plumbers check when they identify low water pressure is whether you have older, galvanized steel threaded water pipes in your home. Galvanized steel will react with copper and brass pipes and fittings. Even if you do not have any copper piping in your house, you will have brass because most valves and faucets are made of brass. The galvanized threaded steel pipes react with the lesser metals and will start to plug up and deteriorate.

The plumber will see the beginning of a rust spot on the surface of the pipe as the deterioration is working its way through the metal. Suspended in most water are particles, chiefly iron and calcium, that do not affect our health but do adhere to each other and to the insides of the pipes causing eventual plug-ups. It may take twenty years or more for that to happen, but it will eventually plug up. The effective inside diameter of the pipe will get smaller and smaller and that is what negatively affects your water pressure.

Another thing an experienced plumber checks is the incoming water pressure level from the city. Those pressures can vary from low pressure to high pressure around each municipality. The ideal water pressure in a house is between 40 pounds per square inch (PSI) and 60 PSI. A plumber can measure that by using a gauge. If the water pressure is too low, St Paul Pipeworks can often overcome this lack of delivery by increasing the inside diameter of the pipes.

They will remove the old pipes and install new ones making sure that the piping is the correct sizing to attain the best water pressure possible for your home. When areas of the city where the pressure delivery is very poor or under 40 PSI, St Paul Pipeworks sometimes will install an oversized main. The re-pipe and pipe replacement helps to overcome the delivery from the city. Occasionally there can be a problem where the pressure level is too high and a pressure-reducing device can be installed. If the water pressure is over 80 PSI, the Plumbing Code in Minnesota requires it to be brought back down to 80 PSI or below.

Sometimes low water pressure is simply a matter of a plug-up. There are service calls where a plumber will go out and find that a kitchen sink is not delivering very much pressure. The plumber will then ask if this is also happening in the bathroom sink and the customer will reply “No, I think the bathroom is fine.” The plumber will look at the kitchen faucet and start by taking the aerator off and cleaning it, and then work backwards until they find where the plug is located. It can get plugged up at the aerator or it can get plugged up if the water supply tubes are too small. Sometimes the whole faucet needs to be taken apart to clean out excess debris or replace the inner parts of the fixture to restore the water pressure.

Various levels of your home may also have various levels of water pressure. The water pressure dramatically reduces the higher that it is pushed up. As you look at your house, you likely will find the best water pressure in the basement, the second-best pressure will be on the main floor, the third-best pressure will be on the second floor, and so forth. In each story of a house, you will lose half of a PSI or around 5 PSI lost for each level of the house. Your plumber will take that into account when they are doing a re-pipe.

If you are having a problem with low water pressure in your home or are just looking for a quality plumber in the St. Paul and Minneapolis metro area, give St Paul Pipeworks a call today.

Yours Truly,

Matthew Dettwiler

Social Media Manager

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