Why would the plumber replace 22mm with 15mm pipe?

aliasojo

Had plumbing work done today and am generally happy with the standard of work done, however sections of 22 mm pipe have been replaced with 15mm and I don't know why.

The main pipes to the bathroom were 22mm with 15mm t's coming off them for the basin taps and the cistern......now they are mainly 15mm with a 22 mm t coming off for the bath taps.

Am I right in thinking this will affect the flow rate? Why would they have done this?

I now have pipework from the ground floor to the upstairs that appears to be a mix of sizes. I not very happy about this, I had a good flow rate previously so I can't think that this is going to be an improvement in any way?

Please tell me it's not been done because 15mm was the only size they had in their van? :rolleyes:

Everything else seemed to be done ok, I'm going to be disappointed if this was a corner cut.

Canucklehead

aliasojo wrote: »

Had plumbing work done today and am generally happy with the standard of work done, however sections of 22 mm pipe have been replaced with 15mm and I don't know why.

The main pipes to the bathroom were 22mm with 15mm t's coming off them for the basin taps and the cistern......now they are mainly 15mm with a 22 mm t coming off for the bath taps.

Am I right in thinking this will affect the flow rate? Why would they have done this?

I now have pipework from the ground floor to the upstairs that appears to be a mix of sizes. I not very happy about this, I had a good flow rate previously so I can't think that this is going to be an improvement in any way?

Please tell me it's not been done because 15mm was the only size they had in their van? :rolleyes:

Everything else seemed to be done ok, I'm going to be disappointed if this was a corner cut.

Hi...usually the OH would tackle this sort of question but here is a link which might help (see the 2 articles on pipe sizing). 15 mm is considerably cheaper than 22mm. Ask your plumber;)

HTH
Canucklehead

aliasojo

Thanks Can. Appreciate the link but I kinda glaze over somewhat when getting into tech spec territory.

I just want to know if I'm right in my thoughts about the flow rate now being reduced with the introduction of 15mm pipe on a previously 22mm pipe run and if they could have been any reason for it other than laziness/corner cutting/cost?

vaio

Yep, smaller pipes will reduce flow but I suppose what is important is does it get reduced below an acceptable value. If the pressure has gone up (say because you’ve gone from stored water to mains) then the flow might even have gone up despite the smaller pipes

macman

Is your flow rate affected by this? Did you agree a spec and if it was written down, did it specify 22mm?
The first thing you need to do is ask the plumber why he used 15mm and get his side of things.
Can't believe any plumber would 'run out' of 22mm.

aliasojo

Both OH and I think the bath is running a little slower now, whether it would still be classed as an acceptable level, I dont know. It's a level less than we had previously to my mind iyswim. (No change in anything other than the pipework btw, system is still the same.)

The plumbers are young lads who are friends of my son so we've not gone down the 'quote route' with exact spec. They are working their way through the house replacing bad work done by a different plumber I got last year and who left me with leaks all over the place.

They're lovely lads, their work is very neatly done, they've taken care and I'm generally very pleased. It's just this one thing that's bothering me. I don't want to upset/offend/fall out with them as they are by far the best workers I've had in this place in 20 years but I dont feel happy with a reduced flow rate no matter how slight.

We used to have a 22mm pipe going to our shower a few years back until the original heating installer changed that to a 15mm for some reason. We noticed a difference but naively didn't link it to the pipework change.

Bit older and wiser down the line and now the same thing has happened with other pipework, I'm just not happy........BUT, I really dont want to be unreasonable with the plumbers.

Will query it with them today but I kinda already know they're going to say 'It's fine, it doesn't matter' etc. But it matters to me. Just need to decide how much, I suppose. :undecided

Thanks for the replies. :beer:

amcluesent

>Why would they have done this?<

Cheaper.

aliasojo

Well if this was simply a cost cutting exercise, it'll be a pity. I'm happy to shell out whatever it takes to get a good, well done (leak free!) job so the increased cost of 22mm over 15mm wouldn't have put me up nor down.

In fact they were going to just buy new connectors for the soil pipe (the glue type) and replace the leaking ones but I told them just to go buy a whole new length of pipe and do away with the joins completely so I would've thought they would've known I wasn't after a 'cheap' job as such.

Will need to have a chat I think.

aliasojo

Update: Turns out they only replaced a small section of the pipe, the rest of the 15mm was already there apparently.

Anyway, they've agreed to replace the whole lot with 22mm so I'm happy and relieved. They really are nice blokes (although whether they moan about me in their van, who knows lol ) and I've never had any issue with their standard of work so I think I'll be keeping these ones and telling everyone else how happy I am with them.

Off to make them coffee.

Thanks for your replies. :beer:

missile

Good result