I have a strange problem. Found a small leak under my sidewalk on the water pipe going into the house… After my plumber repaired it, I think there is another leak nearer the foundation under the front porch. This is a hard place to get to. I have 3/4 inch pipe, and I suggested to him that since we now have easy access to the repair from the original break on into the basement, why can’t I have him slip a 1/2 inch pipe through and connect at both ends? Total length is about twelve feet. The rest of the water line is about sixty feet to the city meter. It is 3/4 all the way. With only my wife and I in the house, I don’t think water pressure is an issue. Opinions? Thoughts? I’m new to the site so I appreciate any help…
Thanks
Was the title supposed to be “waste pipe question”? As it is, it’s a bit of a mangled mess. I’ll ask the mods to fix it for you.
I think it’s supposed to be “water question.” The OP is about a supply pipe, not a waste pipe.
You discussed this with a professional plumber who’s seen the situation at first hand. You’re not going to find anybody here who can give you a better answer than what he told you.
This is a bad idea all around. 1/2-inch pipe for the water service to a house is completely inadequate, and almost certainly doesn’t meet local code requirements. I work for a water utility, and while we do have a lot of 3/4-inch service pipe in our system (installed many decades ago), the minimum size for our new services is 1-inch. Note that 1/2" pipe has only a quarter of the flow capacity of 1" pipe, and less than half the flow capacity of 3/4" pipe. I have never seen 1/2" service pipe to a house in my career. I would have your plumber fix the pipe properly.
I’m skeptical that a half-inch pipe will fit inside the old 3/4" one. And even if it does, that this is preferable to simply replacing the defective length of pipe.
Not having pipes in front of me, I’m pretty sure 1/2" pipe won’t fit inside 3/4" pipe. 1/2" copper might do so.
That aside you’d basically be making an orifice of the 1/2" pipe that would restrict your flow throughout the house. Not a good idea.
I’m going to suggest (in addition to a forum change) that, as you now have had two leaks between the the house and the meter, there is a distinct chance that the old pipe is rotting faster than it can be patched.
Fix it here, and now you have a slightly higher pressure (a leak lowers the pressure downstream) and the higher pressure causes another leak. I’ll give you even money that fixing the new leak will cause yet another.
And no, you can’t use a 1/2" service - no more showers, for one thing.
It is probably a bit past time to replace the entire service from meter to house.
How old is the service (prob. as old as the house)? How deep is the existing 3/4 line?
How deep is the frost line?
I DIY, rent a trench digger and start digging will undoubtedly break the line. Can you live without it for how ever long the replacement takes?
The meter is likely to be the limiting factor is sizing your new service line. If you really have a 3/4 meter, ask the local water department if they’d like to replace the antique meter with a modern one.
If the current meter can handle 1 1/2, install 1 1/2 - go for the largest possible.
Good luck. The term is ‘water service line replacement’. Yes, it IS going to be expensive. But maybe not so much more than repeatably patching a dying, undersized (3/4) service line.
Recommending forum change.
Water service pipe is always copper, in my experience.* Anyway, 1/2" Type K copper pipe has an O.D. of 0.625", so it would fit inside of 3/4" pipe. Still a bad idea.
*While we do have some old wrought iron pipe in our system that was installed during WWII when there were copper shortages, it is a vastly inferior material for water service pipe, and would never be used today…in fact, even during WWII they intentionally installed a slightly larger diameter pipe (1-1/4") so that they could be lined with copper pipe at a later date.
Agree completely. I would recommend replacing the entire water service line on the owner’s side (house to meter/curb stop) with minimum 1-inch copper.
Remember, this is an investment … all the money you spend replacing the water line comes back to you when you sell the place … with interest (hopefully)
As a watcher of “This Old House” for many years I’ve seen them replace several iron pipe water lines with copper. I seem to remember them recently running copper through an iron line, but it may have been an 1 1/4" iron pipe.
Right, I should have been more clear. Copper for water service pipe has been the material of choice at least as far back as the 1930s, continuing up to the present. (Prior to that, the pipe material used could have been anything, from wrought iron to galvanized pipe to actual lead pipe.)
The main exception to the use of copper after the 1930s was the wrought iron cement-lined (W.I.C.L.) service pipe that was installed in WWII due to copper shortages. Most of this has since either been replaced or lined with copper pipe.
So the upshot is that any water service pipe installed after WWII is almost certain to be copper, and most of the older non-copper pipe has either been replaced with copper pipe or lined with copper.
All main pipes fitted by the water supply companies in the UK are plastic these days. They replaced the main feed to my house some years ago and didn’t need to dig a trench as they used a ‘mole’ to get under the block paved front drive.
Been there and done that. Like others have said, replace with copper. Minimum of 3/4", preferably 1" but refer to the code in your area. Using 1/2" is just not enough. You might check to see if Pex is allowed. I do not know if it is permitted for residential supply lines or not but that might be an option. Copper is best, in my opinion.
Why? Copper is more expensive and inflexible. The only downside that I can see is that the joints can be a bit ugly, although that has been improved lately.
As someone who installs underground service lines.
Like others have said 1/2 is insufficient and may not be allowed by code. You’ve now had 2 leaks on the same line. It’s time has passed cut your losses and replace the whole thing before you go through another repair.
HDPE has been used for service lines for decades. It is a completely viable alternative to copper and is better in my opinion. Plenty of plumbers still use copper as a first choice, they are also the same guys that turn their noses up at PEX. It’s more an unwillingness to change than a technical knowledge based decision. Some towns still spec copper, in which case we don’t get a choice.
A majority of my business is well water. It’s been 30 years since anyone in my area used copper for well offset lines. My company has been using HDPE since the 50s. I’ve never had to go back on our work for failing lines, quality of installation is everything regardless of material used. All our lines are run in conduit and sand is trucked in the surround the lines.
The advantage of copper pipe … IMEIO … is that it is stronger. Obviously in the OP’s circumstance the pipe will be buried two feet deep (or deeper) so the strength advantage is not important. However, once inside the house I always insist on “Schedule L” copper, the thick walled stuff. It’s just more rugged than most any plastic. The extra cost is trivial compared to completely replacing one’s plumbing wall, bathroom and kitchen remodels are quite expensive.