New Construction Pressure Testing Protocol

[Levi]

A plumber I worked with pressurized the supply system after each phase, capped it and LEFT it pressurized throughout the entire construction process from rough to final. He explained that it helps him monitor the system for damage from other trades, and discourages homeowners from DIY modifications.

The plumber my folks are working with pressurizes it for inspections (15 minutes) then immediately releases it. He pointed out that code only requires it to hold 50psi for 15 minutes, to be demonstrated for the inspector.

What is typical where you are?

 

[ExtraMilePlumbing]

I'm assuming you're talking about gas line, which we test at 15 psi for 15 min or half of you're gauge for 15 min. Water I believe needs to be only tested at 5 psi

 

[Levi]

It is water supply piping. My understanding is water supply is 50 psi, DVW is 5.

 

[phishfood]

I muich prefer to leave pressure on the water during construction. I can't begin to count the times that someone has damaged a pipe, which was brought to everyone's attention by the leak they created. I have also had to go back later to find and repair leaks that were caused by damage from other trades, that would have been evident at the time of damage if only there were pressurized water in the system.

 

[Levi]

I should get to the point. He has tested it several times but doesn't leave it connected long. He did leave it overnight before the inspection. I checked it several times and noticed it drops about 2 psi per hour. Clearly he was aware of this because he arrived early the next morning and pumped it back up in time for the inspection and immediatly discharged it afterwards. Over 15 minutes, that wouldn't be enough drop to show on the gauge for the inspector. I have not confronted him about this directly as he has made it clear that it only has to hold for 15 minutes, the code agrees, and I am picking my battles (this isn't the only issue with him). Thought a consensus of how it is done may help me decide how to approach this.

This is an air test w/PVC, he has not done a test with water (again not required) and the drywall will go up soon. It is a 1 story on monolithic slab. Does this mean there is definately a leak? How bad a leak would it likely be. I am guessing it is in the slab, because I feel like he would have found it and fixed it if it was above ground.

Edit,
I am ASSUMING it is only air in the lines. He charges it with a compressor via compressor type nipple (not schrader valve) There is no connected water supply (well on site has garden hose, but is not connected to house plumbing yet. He cranks it up to at least 75, and it dropped from 69 to to 52 in about 8 hours (wasn't able to check it before or after that). Another time it went from 73 to 69 in about 1:45, so 2 psi/hr seems consistent.

 

[ExtraMilePlumbing]

From my experience,gas test dropped about 2-5 psi overnight and our journeyman said that's ok, it has to do with evaporation or something like that..

 

[frodo]

air pressure will rise and fall with ambient temperature.

you will notice the pressure is down a couple of pounds in the morning, but as it heats up it will rise back to where it was

I pressure my water pipes to 100 psi and leave them. why dump the test?

I monitor the gauge off and on, then later, I am not flooding a hallway or cutting sheetrock.

if the pressure is dropping and the plumber knows it,,he is a **** plumber. sorry, thats my opinion

2 psi per hour loss of pressure is a leak.

time to break out the soap bottle.

little tip..frig, 50 psi. at that pressure it is to hard to find a leak, pump that bad boy up to 100psi and make that leak
talk to you...wwwwwssssssssssssssssssss!!!!!

 

[Levi]

Thought about the temp drop (it did get cooler during the night) but though 17 degrees in 8 hours went beyond that. I wasn't able to observe it before or after those times.

I considered pumping it back up, but feared I would damage something or be accused of such. Would like to ask GC to have him do an overnight test but I already know the stock answer...it passed inspection and 15 min is all that is required by code. (Inspectors here are notoriously lax)

I suspect the leak is under the slab, because that phase was rushed and MANY other mistakes were discovered and fixed. I feel like he would have found and fixed it if the leak was above ground, but can't find it so he is hoping it will go away. This guy isn't mine to fire. My parents trust the GC, the GC trusts his plumber. I don't trust either one of them which makes me the troublemaker. (I trust lots of people, just not these two)

Any idea how much water this might be, and likelihood that it causes actual trouble? It is a Florida house on sandy soils.

 

[frodo]

when looking for a leak

first culprit is packing nuts, ck them first

2nd is if you have a valve, the pipe itself needs to be capped..valves leak thru

tub spouts need caps, shower heads, washer box valve need caps.
ice maker box needs a cap.
hose bibs need caps.

their should not be any joints under a slab to leak...

 

[ExtraMilePlumbing]

Or Joints on slap must be brazzed ,learned that one from frodo thanks pal. Also find out what type of warranty they're gonna give you , if you suspect a leak in slab,you can pay for leak detection. After the house is finished And have contractor pay if there is one.

 

[Levi]

The shower and tub rough valves are in, but no hosebibs or other valvess yet. everything is just stubbed out, capped and glued. The only copper is the last run into the shower valves.

 

[Chris]

When I install water mains I test to 200psi then drop to 100 because 200 is a high amount of pressure

 

[Mr_David]

I considered pumping it back up, but feared I would damage something or be accused of such. Would like to ask GC to have him do an overnight test but I already know the stock answer...it passed inspection and 15 min is all that is required by code. (Inspectors here are notoriously lax)

.

Who's working for who? They are working for you.
Codes are a minimum standard. Like the plumber you worked with and what phish said. Charging the system with water and leaving it charged is above and beyond what code requires. if you fill it with water and let it sit over night is not an unreasonable request. Find away to have them do it with out pissing them off. Sandy soil will suck up a leak for a will but that leak will grow with time.

 

[Levi]

I can't say enough to thank you guys! A leak was found and repaired. A lot of code violations were flagged by the inspector, so he is having to redo some of the plumbing. When it is reconnected I will insist on a longer pressure test. I think the inspector will be keeping an eye on him as well.

Frodo, I must be confused as to what you mean by joints, the whole supply system is CPVC under slab, so there are many elbows and t's
The only copper is at the shower valves. I think it is soldered not brazed (shiny silver) but I don't know the difference.