Insulating Pipes in new construction

[Richard Hedrick]

Greetings,

I have been having a lively discussion regarding Washington requirement to insulate water supply lines in new construction

Per local code:
PROTECTION FROM FREEZING: Cold water pipes must be insulated to R-3 when installed outside the heated space or in an insulated area. Hot water pipes must be insulated to R-4 [regardless of where they are installed. Backflow devices (usually found on hose-bibbs) must be provided with freeze protection.

Myy question to the plumbers out there is an opinion on the best way to accomplish this in new construction. It seems to me that you could only insulate straight runs between the studs with pipe wrap or foam... that would mean that where the pipe goes thru the stud would not be insulated... opinions appreciated without banter - THANKS

[Jerry Peck]

opinions appreciated without banter

Richard,

Once you've been around here long enough, you will know:

- That few threads are "without banter".

- That the banter often leads to more interesting and informative information on the subject at hand, and other subject too.

- That if you only want what you want the way you want it, this is not likely place you will get it - go to any public forum (this is a public forum) and you will have to live with what goes on during the discussions, if you want any helpful information.

That said (to get past that issue first, don't like it, don't read these threads and posts):

My first recommendation is to check with the local code to see if it strictly addresses "supply" water piping or all water piping.

The IRC and IPC address all water piping: a) supply piping; b) drain piping; and c) vent piping ... as needing to be within the thermal envelope or ... here, I will post what it states:

From the 2006 IRC. (underlining is mine)

- 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.

The 'freeze line' referenced runs approximately from Jacksonville, Florida, through the Florida Panhandle, across the lower part of Texas, then across the very lower parts of New Mexico and California. The rest of the country is within the freeze zone.

What about vents you ask, I did mention vents, right?

P3101.4 Extension outside a structure. In climates where the 97.5-percent value for outside design temperature is 0°F (-18°C) or less (ASHRAE 97.5-percent column, winter, see Chapter 3), vent pipes installed on the exterior of the structure shall be protected against freezing by insulation, heat or both. Vent terminals shall be protected from frost closure in accordance with Section P3103.2.

P3103.2 Frost closure. Where the 97.5-percent value for outside design temperature is 0°F (-18°C) or less, every vent extension through a roof or wall shall be a minimum of 3 inches (76 mm) in diameter. Any increase in the size of the vent shall be made inside the structure a minimum of 1 foot (305 mm) below the roof or inside the wall.


It seems to me that you could only insulate straight runs between the studs with pipe wrap or foam...

Or run the pipes inside the insulation.


that would mean that where the pipe goes thru the stud would not be insulated

Yes, it would mean that.

Run the piping horizontally through the ceiling/floor or ceiling/attic space within the thermal envelope, then turn vertically up through the floor / down through the ceiling.

[Billy Stephens]

Washington requirement to insulate water supply lines in new construction

Per local code:
PROTECTION FROM FREEZING:

Myy question to the plumbers out there is an opinion on the best way to accomplish this in new construction. ... opinions appreciated without banter -


--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.



Slab Construction With Spray foam Insulation. [ Without Banter ? ] * Warning Do Not Click on Attachment to Avoid Banter.

[Gunnar Alquist]

Boy, I'll tell you, my friend Banter Johannsen is pretty upset about being excluded from this discussion! :cool:

Seems to me that if piping is installed within an exterior wall cavity, it will be insulated to a greater degree than R-3, depending on exactly where in the stud wall it is. And, if run in the attic and insulated over with loose-fill fiberglass, would be insulated to an even greater degree.
I wonder if using the foam insulation would be better or worse than the fiberglass wall insulation.

[Billy Stephens]

.
I wonder if using the foam insulation would be better or worse than the fiberglass wall insulation.

It's Prettier , :p
.
Would also make the cavity ( including utility access holes ) air tight.

[Jerry Peck]

Billy,

Your photo makes me wonder ...

Are there any chemical compatibility issues with that foam and ...

- copper piping?

- NM cable outer sheath?

- CPVC piping?

- PVC piping?

- PEX piping?

- ????

[Billy Stephens]

Billy,

Your photo makes me wonder ...

Are there any chemical compatibility issues with that foam and ...

- copper piping?

- NM cable outer sheath?

- CPVC piping?

- PVC piping?

- PEX piping?

- ????

My understanding is after dry time [ apr. 1 hr. ] it's basically a polyurethane foam.

The attached TDS is for the Flame Retardant Mixture.

MSDS would not upload ( over the size limit. )

[Jerry Peck]

Billy,

Even innocent looking things like NM cable outer sheaths are not good when in contact with CPVC BlazeMaster sprinkler piping, and that probably also applies to Flowguard Gold too. http://www.harvelsprinklerpipe.com/caution_areas/pdf/wire_cable.pdf

Possibly even to PVC?

There are so many things which are not compatible with other things ... especially plastic things. http://www.harvelsprinklerpipe.com/caution_areas/pdf/chemical_compatibility.pdf

Those chemicals in that foam are not shown on their chart as either okay or not okay (indicating those chemicals have not been tested with their PVC or CPVC pipe). Technical Support Center—Harvel Plastics, Inc. (http://www.harvel.com/tech-support-chem-chart.asp)

This shows some products which are 'Do not use' products. FGG/BM/CZ™ System Compatible Program (http://www.systemcompatible.com/incompatible.asp)

These are compatible products. Americas - FGG/BM/CZ™ System Compatible Program (http://www.systemcompatible.com/products-Americas.asp)

That foam you posted is not on that list, which does not mean it is 'not okay', but neither does it mean it is 'okay'.

[Billy Stephens]

Mr. Peck,
I'm not seeing any restrictions for standard construction applications ( not that there might not be ) many companies Manufacture their version of this Product including DOW.

Page 4 of the attached Opinion : Crawl Spaces Benefits : Allude to Wiring, Plumbing, Ductwork as an application.

[Jerry Peck]

Billy,

It does not matter how many companies make it, if it has not been tested and approved for chemical compatibility, it cannot be stated that it is compatible.

And that letter sure is not going to do any good on that aspect either.

As I said, *not* being on the approved list, and *not* being on the no approved list, only means it has not been tested.

Does not mean it is not okay, nor does it mean it is okay. It just means you take your chances until testing confirms that it is chemically compatible.

[Billy Stephens]

--It just means you take your chances until testing confirms that it is chemically compatible.
.
You as in the Manufacturer, Architect, Contractor, Installer & PE. ? :D

[Brandon Chew]

This is from one of the links that Jerry posted:



Polyurethane (Spray-On) Foams

We are currently investigating chemical compatibility of polyurethane foams with our CPVC brands. This process will take several months to investigate. Thus, at this time, we cannot say whether such products are compatible with CPVC. While we are not aware of a CPVC failure that was the result of chemical incompatibility with properly applied polyurethane foams, when polyurethane foams are not properly applied there is the potential for excess heat that can lead to ballooning of the pipe and a subsequent failure.

FGG/BM/CZ™ System Compatible Program (http://www.systemcompatible.com/other-compatibility-concerns.asp)

[Jerry Peck]

Brandon,

Thanks, "hide in plain sight", somehow I missed that when I was looking over those lists.

By the way, when I first found those a while back, I was stunned when I read the "Unacceptable Products - Do Not Use" list:

Right there at the top, two very common caulks are listed:
OSI Sealants - Polyseamseal All Purpose Adhesive Caulk
White Lightning - 3006 All Purpose Adhesive Caulk

How often do you suppose those caulks are used to 'caulk around the pipes' where the pipes come out of the wall?

Okay, I'll revise the question: 'When caulked ... '. :)

And what about the Fire Stopping Systems? :(

[Billy Stephens]

This is from one of the links that Jerry posted:

FGG/BM/CZ™ System Compatible Program (http://www.systemcompatible.com/other-compatibility-concerns.asp)

I reserve the right to Revise and Extend my Remarks. ;)