HELP! I’ve Fallen, and I can’t.....OK not really....., but I do need help!

[C4Net]

Hello to all ye sages on this Forum! I really appreciate and thank all involved for this great resource for us serious DIY’ers, or as I like to view us: Students! All I have learned has come from youz guys (and our friends at Code, of course!), so, again, I thank you. But now I’m really at a “T” and don’t know which way to go, so wisdom demands I inquire! I am doing a major remodel of my 1957 Ranch style home. It WAS 1200 sq. ft with a bath & a half. It is now 1650 sq. ft, and we’ve added another full bath which now is ready for plumbing. (I should tell you now that I have pulled Permits for all work being done. I’ve already passed the Drainage (inspection and pressure test) and plan to do the same with the Supply side; No Jack-Leg work goin on here). Now we have always suffered with low water pressure (even though our Static here usu. runs over 60), but didn’t know why. All I knew was that: When 2 people crack open a tap at the same time, the pressure drops dramatically; if 3 do, it drops to nothing. Also knew that the HWH, which is at the farthest point from where the Service enters, is fed by a ½” pipe. But, because 90% of our Supply network was in the attic under a 3-on-12-roof, I knew very little else about how it was plumbed. Well I have since built a new 7-on-12 roof over about 70% of the old roof and cut out much of the old roof deck in those areas. What I’ve found is this: The ¾” Service is immediately reduced down to ½” after only (1) toilet tap. It is then milked by the following ½” branches, in order: #1 serves (2) Lavs & (1) toilet; #2 a tub/shower; #3 is the Kitchen sink. Then it makes a 42’ run toward the poor thirsty HWH... but not before having to split what water is left with the Washing machine and a Hose Bibb! Then the whole thing reverses course and heads back toward the front, supplying the Dishwasher, tub and Lavs with Hot water.
NOW, just from what little I know, there is no way I’m gonna just tap into the ½” lines near the HWH to supply the new full bath without trying to improve my overall setup in what HAS to be considered a poor design/layout. However, some areas are still inaccessible, so a complete replumb, should that be warranted or ideal, is not an option. This system is 100% galvanized pipe. There are a couple of spots in the beginning ¾” where I can cut in to be able to insert PEX adapters. Also, I am planning a complete PEX install on the new supply run

Questions:
1) What if I were to add a ¾” PEX run straight to the HWH to supplement the 1/2” original supply that gets bled to death on it's way there?
2) Along the same thought lines: Would a 3/4” HOT loop back to the Front end of the house help the severe pressure drops we suffer there, especially at shower time?
3) I would like to tie in the Supply runs for the new bathroom at the ideal point and size the pipe correctly. Suggestions?

Any advice is appreciated. Will try to post an isometric sketch or pic here, but if not able, contact me and I will try to send you one. Thanks in advance, Chas. Fournet.

 

[hj]

IF the pressure problem is caused by undersized piping, and that may not be the case, then increasing it SHOULD solve it, but again that may not happen if there are other functional problems.

 

[Sponsor]

 

[MrStop]

It could also be that your galvanized piping is starting to get plugged up.

I'm a "student" as well, and have learned quite a bit (but still a neophyte) over the past few weeks. If you are going to the trouble of repiping, you may want to perform calculations to correctly size your pipes. My older home is similar in that it was plumbed with 1/2" right after the meter. I don't have quite the pressure drops as you. However, you can feel it in the shower if someone flushes.

I believe my small pipe is being aided by shorter runs and higher city water pressure (85 psi). This is not a good thing as the water velocity in the pipes is too high and could lead to noise and premature pipe failure (although it has been in place for about 50 years.

I went through the sizing exercise (See my post here: https://terrylove.com/forums/index.php?threads/water-distribution-re-plumb-advice.59287/#post-439346). What I found is that a 3/4" supply was not enough to where my water pipes split. I would recommend you follow a similar approach.

My setup will be 1" coming from meter to my "mechanical room where it splits off to cold & hot. Cold will maintain 1" to where it splits to a manifold to run to the different rooms via smaller pipes. Hot will be reduced to 3/4" to where it splits to a manifold and run to the different rooms via smaller pipes.

You want to be careful with your new bathroom supply. I'm not sure how far away it is, or if you are planning a recirculation loop. If you go too big without a recirc loop, it will take a long time for hot water to reach the bathroom. So it is best to size correctly - not too big, not too small.

BTW - A couple of questions for you:
1) What did you use to draw the isometric pic?
2) Do you have any details on how you changed your roof pitch? I would like to do the same to my home (currently 4-12 pitch).

 

[C4Net]

IF the pressure problem is caused by undersized piping, and that may not be the case, then increasing it SHOULD solve it, but again that may not happen if there are other functional problems.

HJ,
Thanks for taking your time to help. What 'other functional problems' might be part of the issue?
And what say you about the location and size of the new bath supply taps?

BTW, the drawn lengths of the runs are accurate and proportional.
Attached is a labeled pic of actual 'pretzel piping' cluster for reference...

IF the pressure problem is caused by undersized piping, and that may not be the case, then increasing it SHOULD solve it, but again that may not happen if there are other functional problems.

 

[MrStop]

hj's the pro, but I would guess he's referring to an issue with the galvanized pipes themselves. You can google for some interesting images. Your project may have gotten bigger...


Source: http://www.oldhouseweb.com/how-to-advice/old-plumbing-usually-means-problems.shtml
Old plumbing problem no. 1: galvanized pipes
For a quick test of an old house, turn on the hot water. If the pressure is low, the house probably has galvanized pipes that have corroded and plugged up. The hot-water pipes are the first to go.

The house could have good pressure in the hot-water lines, but still have unseen galvanized-pipe problems. It is possible that only the bad pipes were replaced, leaving lots of old galvanized pipes still in the house and either in need or soon-to-be-in need of replacement.

Experts will tell you to replace the entire piping system when galvanized piping starts to go bad, but that is pricey, and often homeowners opt for the more economical, halfway fix by repairing only the pipe that is the immediate problem. Worse, the bad galvanized pipe may have been replaced with more galvanized pipe instead of copper or plastic pipe, meaning the problem has just been extended, rather than cured.

It's difficult to determine the entire plumbing picture, since most of the system is behind walls. Maxfield says to look under the sinks to get some understanding -- often, plumbers run new pipes up through the floor under the sink instead of through the wall, he says, so you can see where there is new plumbing.

If the house has a crawl space and you're not too discomfited by going into it, you can get a better picture of the plumbing status.

Anytime copper piping has been attached to galvanized pipes, dielectric coupling is required to stop the corrosion caused by dissimilar metals touching. Unfortunately, these junctions may be hidden inside the walls. If a plumber did the replumbing, it certainly should be correct. If it was a do-it-yourself job, the homeowner may not have included the dielectric coupling.

 

[C4Net]

It could also be that your galvanized piping is starting to get plugged up.

I'm a "student" as well, and have learned quite a bit (but still a neophyte) over the past few weeks. If you are going to the trouble of repiping, you may want to perform calculations to correctly size your pipes. My older home is similar in that it was plumbed with 1/2" right after the meter. I don't have quite the pressure drops as you. However, you can feel it in the shower if someone flushes.

I believe my small pipe is being aided by shorter runs and higher city water pressure (85 psi). This is not a good thing as the water velocity in the pipes is too high and could lead to noise and premature pipe failure (although it has been in place for about 50 years.

I went through the sizing exercise (See my post here: https://terrylove.com/forums/index.php?threads/water-distribution-re-plumb-advice.59287/#post-439346). What I found is that a 3/4" supply was not enough to where my water pipes split. I would recommend you follow a similar approach.

My setup will be 1" coming from meter to my "mechanical room where it splits off to cold & hot. Cold will maintain 1" to where it splits to a manifold to run to the different rooms via smaller pipes. Hot will be reduced to 3/4" to where it splits to a manifold and run to the different rooms via smaller pipes.

You want to be careful with your new bathroom supply. I'm not sure how far away it is, or if you are planning a recirculation loop. If you go too big without a recirc loop, it will take a long time for hot water to reach the bathroom. So it is best to size correctly - not too big, not too small.

BTW - A couple of questions for you:
1) What did you use to draw the isometric pic?
2) Do you have any details on how you changed your roof pitch? I would like to do the same to my home (currently 4-12 pitch).

Mr Stop,
Thanks for your Input! Nice to have someone ELSE who has.... BEEN THERE!

Thanks for the link the Sizing info.... I will use that.

Re: your comments, the distance to the New Bath is to scale, each block being 2 ft, either diagonally or up/dn. So in my case it's gonna be about 35' ish to the new fixtures from the HWH.
And yeah, I thought about the length of time it would take to get H from the HWH. It already takes a long time to get H to our Lav. in the very front of the house (the one shown at bottom left), so a HW recirc. pump is probably the way to go. If I'm not mistaken, the piping involved with running such a loop, were I to run it back to the front fixtures, would serve as an additional Supply route for Pressure balancing the Front fixtures during periods of heavy demand, am I correct??
If you, or anybody else reading this, has input on the ideal spot(s) to pipe a HW Recirc. system according to my layout, PLEASE speak up!
["Thirsty Ignorance Knows No Pride" -- Chas. Fournet, 2014]

OH, I forgot to mention!: While I have the entire wall and ceiling area to the left of and above the HWH open at this time, I would like to change out the current 1/2" galv.'d pipe to those fixtures (i.e. the WM, a Sink, and 2 Hose Bibbs; 3=H & 3=C) with a new 3/4" Branch with 1/2" stub-outs, or even 3/8"s to the sink, which is a standard flow Lav.

OH, I forgot to mention!: I don't know if it is Code everywhere or not, but here in Louisiana we have a requirement now to test new Distribution piping to 200 lbs. Now, I kinda have an idea how I can plumb a set of valves and takeoff "T"s right above the HWH, but I welcome input or links to such examples on that, too


Re: the Isometric drawing:
I happen to have an old version of Adobe's Photoshop, V5.5 from about 1998. The Isometric pattern is simply a sample I found online. The way PS works is you build an image in individual Layers, which, except for the Background pattern, are transparent. So as you draw, you can move individual items around, hide, resize, or erase only portions of each layer independent of each other. Then when you are ready, you can 'flatten' it into one image and save it as a .jpg or a .pdf. (see pic)