Insulation on pipes

Yesterday’s last inspection was of a remodeled home (buy and flip) where the seller had installed new CPVC plumbing, but had the foam insualtion on the hot water distribution lines.

It was an unheated basement, so it makes sense (to retain the heat), but I don’t recall ever having seen insulation on CPVC and was wondering if anyone else had. I thought one of the advantages of CPVC was that it has less heat loss than copper tubing, and was curious to see if anyone else thought this odd (or appropriate).

I guess if it is appropraite for CPVC, it would be for PEX, too? Educate me on pipe insulation, please!!!

I wonder how “unheated” the basement is. If it is subject to freezing temperatures in the winter, then no amount of insulation can protect the pipes from freeze damage, unless there is heat tape inside the insulation. You are correct that CPVC pipe will lose heat more slowly than copper, as copper is an excellent heat conductor, and plastic is a moderate to poor heat conductor.

Jim King

Thanks, Jim. That is what I recalled hearing/reading somewhere about CPVC. I am not sure that the intent was to prevent freezing, so much as it may have been to retain heat (less time for hot water to appear at tap).

It was about 75 at the time of inspection, so I can’t vouch for how cold it gets, but there were circulating boiler pipes in the ceiling (also wrapped). I was guessing the guy was either being energy conscious, concerned that it took 30 seconds to get hot water at teh tap, or maybe he was hiding something under the wrap (appeared normal).

Thanks for your thoughts. I will chalk it up to someone going overboard (on a house he was flipping - go figure!)

From my experience, insulated hot water lines is a good indication of someone worried about high hot water and heating bills. I bet my botton dollar both the water and furnace are quite old.

When I went thru plumbing school and we installed CPVC we most often went the extra mile and installed foam insulation tubing on it. Purely for energy reasons.

Pennsylvania Uniform Construction Code… by way of The International Energy Conservation Code and the *International Residential Code *plumbing and mechanical provisions… requires **all **water distribution pipes in unconditioned spaces (both hot and cold), all circulating hot water system pipes, and all mechanical system pipes cabable of carrying fluids above 105 degrees or below 55 degrees to be insulated regardless of the type of pipe.

This means that PEX, copper, CPVC or any othe type pipe either in an unconditioned space or carrying heated or cooled fluids to be insulated in all cases.

Well there you go, then! Apparantly he was not so much concerned with energy efficiency as he was following code. (The heater and water heater were both 2006).

Did not know that about all pipes being required to be insulated in unheated space, but I will be sure to call it out in all the new construction I see without it!:wink: Thanks!

From the 2006 International Residential Code (Plumbing Section)):

Energy conservation provisions apply to pipes carrying heated or cooled liquids under the 2006 International Energy Conservation Code (IECC).

Protection from freezing applies to ALL pipes carrying liquids that can freeze, and applies for all climates in Pennsylvania.

This includes sewer pipes, waste pipes, water distribution pipes, condensate pipes, etc…anywhere in the structure that is not ‘conditioned’ by design or default.

Whomever did this remodel appears to have only been concerned with his water fro the water heater not losing heat on its way to the outlet.

Doesn’t appear to have been a lick concerned about pipes freezing in an unheated basement in winter.

But then again, Pennsylvania Uniform Construction Code exempts alterations, renovations and repairs from compliance with State codes, unless the local municipality chooses to enforce the Code for alterations, renovations, and repairs.

As a home inspector, you should cite any pipe that carries liquids in an unheated space as subject to freezing and damage in Pennsylvania regardless of the UCC Code.

I have NEVER, ever, seen a sewer or waste line insulated in PA. Not even once, in over 2000 inspections.

I have. It’s done all the time.

The key phrases in the code is where the “pipes are subject to freezing” and "unless adequate provision is made to protect it from freezing by insulation by heat or both."

Not all ‘unheated’ spaces will necessarily freeze. Basments and crawlspaces without heat may still be kept above 32F by default from heat radiated into them from above when the floor isn’t insulated, for example.

So pipes do not need to necessarily be insulated where the space is kept above 32F…

Pipes in areas subject to freezing can be heated with heat tape…and that is a VERY common sight in my part of the state.

For new construction, the Plumbing Code requirements I cited forces designers to rethink their designs to make sure they are no longer running pipes in areas subject to freezing…so the wastes, drains, supplies, etc are run in conditioned spaces…not areas where they can freeze.

For existing construction, there is no requirement to go back and ‘force’ previously non insulated pipes to become insulated…but many DO do just that.

The building sewer is not required to be insulated provided it is installed at usually about 18" below grade. Builder sewers underground can be installed at higher than frost depths in most cases because the chronic running of hot water through such pipes keeps them open.

Quite common to see insulated building drains, water distribution pipes, and other waste lines insulated or heat taped in crawlspaces and basements of Pocono vacation homes for example.

So, yes, you probably see the same thing in your region, but it really didn’t grab your attention.