Low water pressure
Discussion
Been in current house for a number of years, the water pressure started off barely okay and it feels like over time it has steadily gotten worse to the point that if somebody is in the shower and you flush the toilet the shower falls to a trickle. Of course the getting worse is subjective, never have tested or checked it.
Never really had this issue in other houses before so not quite sure where to begin on fixing, its in a hard water area but it feels like its more down to the supply into the house rather than the pipework in the house, is it a water company problem if that is the case & can you get them out to do an assessment to see if it meets a minimum criteria if such a thing exists?
Never really had this issue in other houses before so not quite sure where to begin on fixing, its in a hard water area but it feels like its more down to the supply into the house rather than the pipework in the house, is it a water company problem if that is the case & can you get them out to do an assessment to see if it meets a minimum criteria if such a thing exists?
First question is do you have a header tank and immersion, or direct mains to a combo boiler? I suspect the latter and you've a mains pressure issue. Is the stop cock valve fully open? If so pressure test and flow rate would be the first thing to check. Then the valve from the meter to the house, check if fully open. Then call to water co. to check the pressure at the meter, as that could have an issue.
Sounds exactly like my daughter’s house. You’ll probably find that the static pressure is OK, but flow rate is poor. She involved the water company who tested everything of theirs and found no problem, probable partial blockage somewhere on her property. They quoted (iirc) £12,000 to run a new supply pipe from the stop-cock in the street with no guarantee that it would be a fix if the blockage was in the house.
Your experience will depend on both the mains water pressure and flow rate. Unfortunately the legal minimum pressure is 0.7bar which is no good for very much. Most companies aim for 1.0bar minimum (and you might get a lot more) but in these days of water companies squeezing every penny in dividends a lot have reduced pressure to lower leakage rates (rather than fixing the issue).
If you have low pressure and/or flow and a pressurised (unvented) system then you can change to a traditional vented system with hot & cold tanks and eg pumped showers.
If that’s not good enough then the next step up is to have a break tank (a very large reservoir of reserve water fed from the mains) and then downstream of that some heavy duty balanced pumps to effectively create your own local high pressure & flow system “mains” which can then run an unvented system.
First step is to ask your water company what they think they supply to you, and/or measure it yourself.
If you have low pressure and/or flow and a pressurised (unvented) system then you can change to a traditional vented system with hot & cold tanks and eg pumped showers.
If that’s not good enough then the next step up is to have a break tank (a very large reservoir of reserve water fed from the mains) and then downstream of that some heavy duty balanced pumps to effectively create your own local high pressure & flow system “mains” which can then run an unvented system.
First step is to ask your water company what they think they supply to you, and/or measure it yourself.
Got any new build estates in your area? You're not Thames water by any chance.
We had a huge new build estate near us a few years back, and they came and fitted additional valves leading into the area I live in, dropping water pressure to about 1000 homes, because they couldn't deliver otherwise to the new homes.
And now we are daily getting texts and emails from Thames Water saying how they are pushed to deliver water, and our water pressure has dropped. I suspect they've turned down supplies again.
We had a huge new build estate near us a few years back, and they came and fitted additional valves leading into the area I live in, dropping water pressure to about 1000 homes, because they couldn't deliver otherwise to the new homes.
And now we are daily getting texts and emails from Thames Water saying how they are pushed to deliver water, and our water pressure has dropped. I suspect they've turned down supplies again.
Basic things to check include
Are all stopcocks turned fully on?
Is there a pressure reducing valve in the house?
What pressure do the neighbours get?
What is the flow rate in litres/min from the kitchen tap? Ditto outdoor tap if you have one?
Previous house had a pressure regulating valve hidden in the downstairs loo, it was required to keep the pressure fed to the combi at 3 bar or so, but as it got old and full of crud, it reduced the flow.
Also the old combi had a mesh filter on its input which was furred up.
Are all stopcocks turned fully on?
Is there a pressure reducing valve in the house?
What pressure do the neighbours get?
What is the flow rate in litres/min from the kitchen tap? Ditto outdoor tap if you have one?
Previous house had a pressure regulating valve hidden in the downstairs loo, it was required to keep the pressure fed to the combi at 3 bar or so, but as it got old and full of crud, it reduced the flow.
Also the old combi had a mesh filter on its input which was furred up.
First thing to check is if your neighbours are also having issues and if it varies by time of day, if so then it's likely a wider issue and not localised so chasing gains from replacing the pipework inside the house likely won't yield results.
I had similar (used to take half a minute to fill the kettle to brim and sometimes the washing machine would error out due to low flow rate) but the neighbors pressure was fine, it turned out to be a scaled up stopcock the incoming pipe is lead so likely was at least 40 years old.
Once the stopcock was replaced the water pressure increased and can now use sprinklers in the garden, before the pressure wasn't enough to power them.

I had similar (used to take half a minute to fill the kettle to brim and sometimes the washing machine would error out due to low flow rate) but the neighbors pressure was fine, it turned out to be a scaled up stopcock the incoming pipe is lead so likely was at least 40 years old.
Once the stopcock was replaced the water pressure increased and can now use sprinklers in the garden, before the pressure wasn't enough to power them.
Byker28i said:
Got any new build estates in your area? You're not Thames water by any chance.
We had a huge new build estate near us a few years back, and they came and fitted additional valves leading into the area I live in, dropping water pressure to about 1000 homes, because they couldn't deliver otherwise to the new homes.
And now we are daily getting texts and emails from Thames Water saying how they are pushed to deliver water, and our water pressure has dropped. I suspect they've turned down supplies again.
Thames Water reduced the pressure in parts of my neighbourhood due to leaks (have caused two massive road and house destroying sink holes in the last 5yrs). Pressure to my house is OK but not great. A plumber remarked it seemed low.We had a huge new build estate near us a few years back, and they came and fitted additional valves leading into the area I live in, dropping water pressure to about 1000 homes, because they couldn't deliver otherwise to the new homes.
And now we are daily getting texts and emails from Thames Water saying how they are pushed to deliver water, and our water pressure has dropped. I suspect they've turned down supplies again.
AndyTR said:
First question is do you have a header tank and immersion, or direct mains to a combo boiler? I suspect the latter and you've a mains pressure issue. Is the stop cock valve fully open? If so pressure test and flow rate would be the first thing to check. Then the valve from the meter to the house, check if fully open. Then call to water co. to check the pressure at the meter, as that could have an issue.
Direct mains and combi boiler is the setup, bungalow and no tanks anywhere.Stop cock is fully open, was replaced within the last 6 months as the previous one was leaking. It didn't have much affect on the pressure.
Will call water company and ask them to do a pressure check, are they able to check the flow rate from the water meter to the stop cock?
littleredrooster said:
Sounds exactly like my daughter s house. You ll probably find that the static pressure is OK, but flow rate is poor. She involved the water company who tested everything of theirs and found no problem, probable partial blockage somewhere on her property. They quoted (iirc) £12,000 to run a new supply pipe from the stop-cock in the street with no guarantee that it would be a fix if the blockage was in the house.
£12k?! lucky at the moment the driveway is just gravel and soil so easy for me to hire something and dig up Who's responsibility is the supply from the road into the house? What did she do in the end?
Neighbours have previously commented on the low pressure but a lot of them have already had houses renovated so suspect they have systems in place like mentioned about to mitigate the low pressure/low flow into the house.
Doesn't vary by time of day is always low.
No hidden pressure reducing valves, system is actually quite simple feed into house > stop cock > pipes to boiler and then direct to kitchen and bathroom.
Think I'll get onto the water company and see what they say, will also check at the water meter if the that is fully open
Doesn't vary by time of day is always low.
No hidden pressure reducing valves, system is actually quite simple feed into house > stop cock > pipes to boiler and then direct to kitchen and bathroom.
Think I'll get onto the water company and see what they say, will also check at the water meter if the that is fully open
bobski1 said:
£12k?! lucky at the moment the driveway is just gravel and soil so easy for me to hire something and dig up
Who's responsibility is the supply from the road into the house? What did she do in the end?
Her land = her responsibility apparently. It’s still an ongoing issue.Who's responsibility is the supply from the road into the house? What did she do in the end?
John D. said:
Thames Water reduced the pressure in parts of my neighbourhood due to leaks (have caused two massive road and house destroying sink holes in the last 5yrs). Pressure to my house is OK but not great. A plumber remarked it seemed low.
Some companies are also currently lowering their pressure to try to reduce consumption as (due to the heat) demand is high and stock is getting low. Will also help with the leaks too, as already mentioned.xx99xx said:
John D. said:
Thames Water reduced the pressure in parts of my neighbourhood due to leaks (have caused two massive road and house destroying sink holes in the last 5yrs). Pressure to my house is OK but not great. A plumber remarked it seemed low.
Some companies are also currently lowering their pressure to try to reduce consumption as (due to the heat) demand is high and stock is getting low. Will also help with the leaks too, as already mentioned.Had the water company out who confirmed it’s above their minimum levels for flow and pressure. It’s not just a recent problem because of the heat, the guy that came out confirmed it’s been quietly getting tweaked down for years.
We are in the process of installing a tank and booster pump that should get us from just over 1bar to over 3.
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