Baseboard Heating- PEX vs Copper

[Allan12]

All,

I'm considering switching over my forced hot air system to baseboard heat as part of a major remodel.

However, I'm torn wether to have baseboard heating installed with PEX or COPPER.

I've heard the copper retains the heat better than the pex, but it's much more expensive. Also pex is apparently more durable.

Please let me know your thoughts.

-A

[adamthesmythe]

You're talking about the tubing going to the baseboards, right?

If so- the heat capacity of the tubing is probably not very significant compared to the heat capacity of the water it contains.

Now if you want heat retention- nothing better than cast iron radiators, with cast iron baseboards second best.

[whaleknives]

Yes, I think you want to look at the construction of the baseboard heating fins, and not the connecting piping. Plastic has such a lower thermal conductivity than metal, it's hard to imagine a plastic heating surface. The relative size would be enormous.

[Allan12]

Yes, I mean the tubing going into the baseboards.

The contractor told me to decide on pvc vs pex.

Does that only apply to the water tubing or the fins as well? I would imagine all baseboard units would have metal fins?

[dpc]

I'm not really clear on your question. We have radiant underfloor heating. It uses PEX for the hot water but has aluminum radiator fins that clip onto the PEX and attach to the underside of the subfloor.

If PEX is allowed, I think it is superior to copper and less expensive, so that is what I would do. If anything the PEX should improve the efficiency of hot water heating since it will lose less heat, leaving more for the radiator - whatever it is.

[Toons]

FYI:
Why Pex is better

http://www.sharkbite.com/resources/faqs/pex-tubing/

[batpot]

pex should be cheaper than either PVC or copper, and won't be prone to pinhole leaks like copper can be.

[Allan12]

I'm not really clear on your question. We have radiant underfloor heating. It uses PEX for the hot water but has aluminum radiator fins that clip onto the PEX and attach to the underside of the subfloor.

If PEX is allowed, I think it is superior to copper and less expensive, so that is what I would do. If anything the PEX should improve the efficiency of hot water heating since it will lose less heat, leaving more for the radiator - whatever it is.

I'm talking pex related to baseboard heating.

[tombauer]

How long do you plan on living there? Pex would certainly be less expensive. As for pinhole leaks in copper, there are at least two weights or thicknesses of copper, the heavier grade is less subject to pinhole leaks, but certainly more expensive. I have never heard of rodent damage to copper compared to pex. Pex certainly has its advantages with its flexibility compared to the various elbows and joints needed for the copper installation.

[packet]

...The contractor told me to decide on pvc vs pex.

pvc is not copper, it's another type of plastic... don't let the contractor use it, go with the pex.
pex will also be better than copper for this purpose.

Does that only apply to the water tubing or the fins as well? I would imagine all baseboard units would have metal fins?

The baseboard units should be all metal of some kind, the fins will not be plastic (unless some cruel joke is being played).

Disclaimer... I am not a pro. I'm just and fairly experienced diy'r. I've installed radiant floors with pex as well as lots of other copper plumbing.

If you haven't already picked the baseboard units, go with cast iron (as stated above) if possible.

Good luck!

:beerCheers,
packet

[Allan12]

...The contractor told me to decide on pvc vs pex.

pvc is not copper, it's another type of plastic... don't let the contractor use it, go with the pex.
pex will also be better than copper for this purpose.

Does that only apply to the water tubing or the fins as well? I would imagine all baseboard units would have metal fins?

The baseboard units should be all metal of some kind, the fins will not be plastic (unless some cruel joke is being played).

Disclaimer... I am not a pro. I'm just and fairly experienced diy'r. I've installed radiant floors with pex as well as lots of other copper plumbing.

If you haven't already picked the baseboard units, go with cast iron (as stated above) if possible.

Good luck!

:beerCheers,
packet

You're right, copper. Don't know where I got pvc from!

This is the house that I plan on spending my whole life in.

I haven't picked the baseboard units does lowes/Hd sell cast iron units?

[orlandoman]

Suggest checking with your homeowners ins. co., here in FL at least two insurers. will not insure homes with pex.

"PEX, cross-linked polyethylene, piping is not acceptable. Our extensive claims data indicated that PEX piping is prone to leaking and often results in significant water damage. Please review 4-point inspections and do not submit risks with PEX pipes."

[packet]

Suggest checking with your homeowners ins. co., here in FL at least two insurers. will not insure homes with pex.
"PEX, cross-linked polyethylene, piping is not acceptable. Our extensive claims data indicated that PEX piping is prone to leaking and often results in significant water damage. Please review 4-point inspections and do not submit risks with PEX pipes."

An excellent recommendation!

But, I must say... wow... really? ... unbelievable... :/ ... any idea when that was written? And about what PEX type specifically?

About where to buy, I don't know as I've never shopped for them.
I just recovered a dozen or so old cast iron (steam) radiators from an old factory that I intend to convert to water and connect all up with pex... They were free! I still can't believe they were going to toss them!. I too plan to convert forced hot air to water/radiators...

:beerCheers,
packet

[orlandoman]

Suggest checking with your homeowners ins. co., here in FL at least two insurers. will not insure homes with pex.
"PEX, cross-linked polyethylene, piping is not acceptable. Our extensive claims data indicated that PEX piping is prone to leaking and often results in significant water damage. Please review 4-point inspections and do not submit risks with PEX pipes."

An excellent recommendation!

But, I must say... wow... really? ... unbelievable... :/ ... any idea when that was written? And about what PEX type specifically?

About where to buy, I don't know as I've never shopped for them.
I just recovered a dozen or so old cast iron (steam) radiators from an old factory that I intend to convert to water and connect all up with pex... They were free! I still can't believe they were going to toss them!. I too plan to convert forced hot air to water/radiators...

:beerCheers,
packet

In February/March 2015, while compare H.O. quotes, I got one from Tower Hill Insurance Co. I have 8 inches if PEX in the line from my water heater, in my garage, to the water line, 4 inches on both the cold & hot water line. Had to have a 4-Point inspection for them to review. There were pictures of the PEX in the report. I was told I would have to replace the 8 inches for a policy with Tower Hill ... yes, I know, crazy. Didn't go with Tower Hill.

[c078342]

I've heard the copper retains the heat better than the pex

. On the contrary, copper is a great conductor of heat. The thermal conductivity (k, BTU/hr/deg F/ft) of copper is about 800 times higher than that of PEX. So hot water flowing through copper tubing will conduct (lose) heat to its surrounding much, much faster than PEX. I've had a PEX water system for 8 years and have no complaints or leaks. Plus it is very easy too make modifications.

[gmc4h232]

Suggest checking with your homeowners ins. co., here in FL at least two insurers. will not insure homes with pex.
"PEX, cross-linked polyethylene, piping is not acceptable. Our extensive claims data indicated that PEX piping is prone to leaking and often results in significant water damage. Please review 4-point inspections and do not submit risks with PEX pipes."

An excellent recommendation!

But, I must say... wow... really? ... unbelievable... :/ ... any idea when that was written? And about what PEX type specifically?

About where to buy, I don't know as I've never shopped for them.
I just recovered a dozen or so old cast iron (steam) radiators from an old factory that I intend to convert to water and connect all up with pex... They were free! I still can't believe they were going to toss them!. I too plan to convert forced hot air to water/radiators...

:beerCheers,
packet

In February/March 2015, while compare H.O. quotes, I got one from Tower Hill Insurance Co. I have 8 inches if PEX in the line from my water heater, in my garage, to the water line, 4 inches on both the cold & hot water line. Had to have a 4-Point inspection for them to review. There were pictures of the PEX in the report. I was told I would have to replace the 8 inches for a policy with Tower Hill ... yes, I know, crazy. Didn't go with Tower Hill.

Are you sure your HOI people aren't confusing Polyethylene PEX piping with Polybutylene QUEST piping? PEX is good stuff while QUEST is the subject of many class action lawsuits. They look similar to the untrained eye. I don't think you can buy QUEST piping in the US anymore.

As far as what pipe to use for baseboard heat, I would vote for PEX, and it should be oxygen barrier PEX or PEX-AL-PEX with PEX-AL-PEX being preferred. This will help prevent corrosion of any iron containing components in your heating system i.e. old school radiators. My reasons are as follows:

1. PEX is cheaper
2. PEX is not subject to corrosion from acidic well water like copper.
3. PEX is flexible while copper is not - this means less joints, which means less potential for leaks.
4. PEX also is slightly more resistant to bursting from freezing due to its aforementioned flexibility - not much, but some.
5. Polyethylene likely has a higher R-Value than copper (copper is a conductor of both electricity as well as heat), so slightly less heat loss. This isnt a big deal IMO because either material can be insulated to retain heat.