pex insulation

[robert smith]

i have a pex manifold surface mounted (on the drywall) in a utilty closet. the wall that this manifold is mounted on happens to be an exterior wall. an inspector has informed me that i need to insulate the pex lines at this location. he says the code explicitly specifies "pex shall be insulated within 24" of an exterior wall"

this closet is inside the climate controlled living area of my house. my living area will never freeze, especially in south texas. this doesn't make any sense. can anyone expand on this code requirement or if it even exists?

[Aaron Miller]

The supply piping requires insulation in order to protect it from freeze damage as per IRC P2603.6 and/or the PEX manufacturer. P2603.6 Freezing. In localities having a winter design temperature of 32°F (0°C) or lower as shown in Table R301.2(1) of this code, a water, soil or waste pipe shall not be installed outside of a building, in exterior walls, in attics or crawl spaces, or in any other place subjected to freezing temperature unless adequate provision is made to protect it from freezing by insulation or heat or both. Water service pipe shall be installed not less than 12 inches (305 mm) deep and not less than 6 inches (152 mm) below the frost line.

[Scott Patterson]

i have a pex manifold surface mounted (on the drywall) in a utilty closet. the wall that this manifold is mounted on happens to be an exterior wall. an inspector has informed me that i need to insulate the pex lines at this location. he says the code explicitly specifies "pex shall be insulated within 24" of an exterior wall"

this closet is inside the climate controlled living area of my house. my living area will never freeze, especially in south texas. this doesn't make any sense. can anyone expand on this code requirement or if it even exists?

Is the utility closet inside the home? If it is on the drywall is there insulation behind it in the stud cavity/bay? Manifolds that I have seen are usually in the conditioned airspace of the home or an area that will not freeze. With you being in Houston, you could just about have the PEX on the back porch of the house and it wouldn't freeze! ;)

[robert smith]

aaron, if this is the code, i don't see a "within 24 inch of an exterior wall" (as the inspector quoted) anywhere in there.
scott, the closet is inside the house, on the drywall of an insulated exterior stud wall. you're right, freezing is normally not our biggest problem in houston; especially inside my house. i'd be more concerned about the invisible fire outside!
still think if that 24 inch rule is actually code, it's a dumb code. thanks, guys.

[Scott Patterson]

aaron, if this is the code, i don't see a "within 24 inch of an exterior wall" (as the inspector quoted) anywhere in there.
scott, the closet is inside the house, on the drywall of an insulated exterior stud wall. you're right, freezing is normally not our biggest problem in houston; especially inside my house. i'd be more concerned about the invisible fire outside!
still think if that 24 inch rule is actually code, it's a dumb code. thanks, guys.

If it is inside the conditioned part of the home and on an insulated wall then it is a moot point.

Ask the inspector to cite the specific code that would not allow for this.

I know of no code or manufactures requirement that would not allow this type of install. Now if it was in an unconditioned/uninsulated garage or storage room then it would be an issue.

Yes, codes do not always equal common sense!

[Jim Robinson]

I've never heard of any 24 inch rule. That's just silly. You would have to insulate a toilet line inside the bathroom if it came up through the floor of the bathroom. I'd ask, politely, to see the rule in writing. No need to antagonize the inspector if you'll need him later.

[Jerry Peck]

The supply piping requires insulation in order to protect it from freeze damage as per IRC P2603.6 ...

Aaron,

Nope, it does not say that - go back and read it again. ;)

Also read P3103.2.

[Jerry Peck]

In localities having a winter design temperature of 32°F (0°C) or lower as shown in Table R301.2(1) of this code ...

Table R301.2(1) refers you to Appendix D of the IPC, and Appendix D shows that 32°F line right about ... (I'm sure you've heard me say this before) ... right about along I-10 (Interstate 10) from Jacksonville west.

In other words, not much of the country is not included in being above that "I-10 freeze line" (as I refer to it - you've probably heard me say that before too). If you are near or above I-10, you should be adhering to the freeze protection sections of the code - or at least checking to see where you are located in relation to Appendix D areas.

[Aaron Miller]

Aaron,

Nope, it does not say that - go back and read it again. ;)

Also read P3103.2.
Are you claiming that supply plumbing requires no insulation?

[Jerry Peck]

Are you claiming that supply plumbing requires no insulation?

Nope. ;)

I'm simply pointing out that you have *added words* which are not in there, and in doing so you are *limiting* what you say the code calls for to less than what is actually in the code. :p

Go back and read it again, and read that other section too. :)