Plumbers: PEX or Crimp?

SV reX said:

93gsxturbo said: Its all about the proper item for the application. 

I honestly can't think of any residential applications where copper is a better choice than PEX. 

Polybutylene has entered the chat.  

In reply to 93gsxturbo :

No comprendo. 
 

Polybutylene is a completely different product than PEX (and obsolete because of failure rates)  It's been completely removed from the market.

Thats like saying "asbestos siding has entered the chat". 

Its more like saying "just because it looks good in 10 years doesn't mean it will look good in 20".  Copper and iron, even with their faults, are established products with known failure modes and shortcomings.  Polybutylene was hailed as a viable option for almost 20 years, right up until it wasnt.  Pex has been around longer but still has only been popular for potable water piping for 25 years or so.  

As a man in the biz, I am surprised there is not more hesitation toward "the next big thing".  Think back to how many steps forward end up with steps back.  Aluminum wiring, Polybutylene, asbestos, so on so forth.  Guess it doesnt really matter when you are building a house for someone else, once its not your problem, its not your problem.

I don't know that there are nearly as many steps back as there are steps forward. People like to hype old houses, and I enjoy the character, but modern building materials have made a tight, solid structure for a reasonable price. I sure know which one I'd like to pay to heat in the debate over a modern house versus a board and tar paper shanty insulated with straw. Which is where we'd be if we didn't keep trying these steps forward.

In reply to dculberson :

I had to laugh and share.

I was looking at insulation value rates thinking about upgrading the house somehow. The loose vermiculite in my walls and ceiling is only 3-4 points higher in R value than actual bales of straw. 

93gsxturbo said:

Its more like saying "just because it looks good in 10 years doesn't mean it will look good in 20".  Copper and iron, even with their faults, are established products with known failure modes and shortcomings.  Polybutylene was hailed as a viable option for almost 20 years, right up until it wasnt.  Pex has been around longer but still has only been popular for potable water piping for 25 years or so.  

As a man in the biz, I am surprised there is not more hesitation toward "the next big thing".  Think back to how many steps forward end up with steps back.  Aluminum wiring, Polybutylene, asbestos, so on so forth.  Guess it doesnt really matter when you are building a house for someone else, once its not your problem, its not your problem.

Not understanding your argument.  You're saying that "the next big thing" with 25 years of proven superiority is... inferior... just because it's new?  I don't think the "get off my lawn" argument works for PEX.

In reply to 93gsxturbo :

You are basically saying "We've always done it that way, so it must be best".  The science says otherwise. 
 

Just because there are houses with copper in them that is 50 years old doesn't mean copper is best. There are also situations where copper starts springing leaks in 6 months. 
 

I've been remodeling for over 45 years. I've never cut open a galvanized pipe that WASN'T rusted   .  
 

PEX has only been in widespread use in the US for about 20 years, but it has been used in Europe since the early 1970's. It has already been proven.  It's not "the next big thing".

And as a man in the business, inferior products or methods will ALWAYS remain my problem. I stand by my work, and if I EVER thought houses I built had used inferior materials, I would stand by my work. Your suggestion otherwise is not only insulting, it is a total load of crap. 

RevRico said:

In reply to dculberson :

I had to laugh and share.

I was looking at insulation value rates thinking about upgrading the house somehow. The loose vermiculite in my walls and ceiling is only 3-4 points higher in R value than actual bales of straw. 

That's pretty funny! Worth noting, of course, is that vermiculite insulation is wildly obsolete, dating back to not much later than when straw bales were in use. It stuck around to some extent until ~1990 but I don't believe it's been commercially sold for homes since then, which is 32 years ago.

Also, when you're at what R1? 3-4 points of R value make a huge difference.

RevRico said:

In reply to dculberson :

I had to laugh and share.

I was looking at insulation value rates thinking about upgrading the house somehow. The loose vermiculite in my walls and ceiling is only 3-4 points higher in R value than actual bales of straw. 

I'm curious if that is an R rating per inch, or overall wall performance?

Straw bale walls are usually REALLY thick (like 18") with overall wall R ratings of R50 or more. 

In reply to SV reX :

they would be per inch if I'm reading this chart right. Shame there isn't an easy way to get it out of the walls.

Link to the full chart I found

I was looking around to see if it would be worth cutting some foam board to fit my kitchen cabinets because you can feel the cold coming through when you open them and my jars of sauce actually need to warm up before use during the March February cold spells. 

To tie this back to the original topic, sort of, would it be worth insulating hot water pipes/pex? Could it cut down on the time it takes to get hot water to the faucets or just be a waste of time?

Insulating long runs of hot water PEX just means the water coming out is warm until you hit the hot stuff. Instead of being cold for the same time. In my experience, even with a faucet just a few feet from my DHW, it's still cold/warm for about 10 second before I hit the hot water. My buddy has got a re-circ loop and at the opposite end of his house his kitchen faucet will produce hot water in less time. 

If you want hot water instantly, start planning your re-circ loop. 

It's my understanding that insulating the lines is more about keeping the cold out - ie, freeze protection. 

There was a huge recall of plastic tubing that was being used in radiant slabs a number of years ago. Does anyone recall the details therein?

Kreb (Forum Supporter) said:

There was a huge recall of plastic tubing that was being used in radiant slabs a number of years ago. Does anyone recall the details therein?

That was polybutylene.  Different stuff. 

In reply to pheller :

You're right about the recirculating loop, but there is a difference between copper and PEX regarding thermal transfer. 
 

Copper is a conductor. It conducts the heat from the water to the outside. PEX doesn't do that. 

In reply to RevRico :

That's a really good chart. Although, a little unusual. For example, the calculations are for an actual 4" thickness of wall cavity. Wall cavities are 3 1/2", and fiberglass is manufactured 3 1/2" thick. So there is no such thing as R-14.8 fiberglass batts.  Similarly, there is no such thing as a 4" thick straw bale.  But still excellent info. 
 

You are reading it a little incorrectly. The large R value difference between vermiculite and straw bales is for a 4" thick wall. The difference per inch is R-2.13 per inch for vermiculite, and R-1.45 for straw bales. 
 

Yes, foam board will help in your cabinets. Partly because of the R value, but mostly because it's a great draft sealer.

In reply to pheller :

If you have a recirculating loop, you should insulate it to minimize heat loss during the circuit.  That water will have to be re-warmed every time it goes back into the heater.

If it is a typical dead-end branch, you're right.  Insulating it is of minimal value and only saves a little energy loss when you're actually using it, instead of continuous.

In reply to Duke :

Do you think there is a difference between copper and PEX regarding insulating?

SV reX said:

In reply to Duke :

Do you think there is a difference between copper and PEX regarding insulating?

Absolutely.  There is a reason they put copper on the bottom of cooking pans - heat conductance.

The PEX will definitely lose far less heat in transit.

In reply to Duke :

We are on the same page on that one

In reply to SV reX :

Do people still used galvanized pipe?   If we managed to update our wiring to not have knob & tube, the modern insurance would not allow any galvanized pipe.  

(can't help much with the rest of this, although we did use PEX in our camper rebuild.  Loved it.)

In reply to alfadriver :

Not really.  Sometimes we use it  in industrial and commercial work. 
 

The only reason I've mentioned it is because the OP is talking about repair work on older homes in the Pittsburgh area, and it's highly likely he will run into it. 
 

No reason to talk about it for new piping. 

I've never used plastic for supply, only drains. I have a mountain cabin that periodically has a pipe or two burst from freezing. Is there any significant difference between PEX and copper/Iron IRT resistance to splitting due to freezing?

In reply to Kreb (Forum Supporter) :

Yep. Metal splits when it freezes. PEX doesn't. 
 

PEX expands enough to survive freezeups. 

I had one PEX split on me, but in its defense it was completely full of water and it saw -29F for an extended period. (RV that gets left in Ontario).  I had to leave the RV in the early fall for a family emergency with the expectation of making it back up for another week or two.  I didn't, and it sat all winter with water in it.  I figured I'd roll the dice instead of making a 1000 mile trip when I really didn't have the time.  I don't think it was solely the expansion that killed it, but at -29F, I would imagine the PEX got pretty brittle.

The real upside is that it was a 15 minute fix with a couple sharkbites and a foot of tube.

Compare that with copper that will split after a couple hours at 25 degrees ambient and it's not really a comparison at all.

Thanks all, sounds like PEX is the answer. 

To answer some questions, why do I not like sweating copper? Well, most of the work that I am doing is inside old walls, or in basement ceilings, or along basement walls. Its a PITA to have open flame so close to old wood and new paint. Yes, I use things to protect finishes and prevent fires, but still. These are old houses, so when a tenant moves out I foresee having to re-do some bathrooms and kitchens over the next few years. Having a quick and easy way to run new lines to where I want would be good. 

So why run new lines? Well, take the house I am working on now. Every joint in the main supply line is galvanized steel. Yes, copper pipe, sweated to a threaded fitting, then screwed into a galvanized elbow or tee. Every. Joint. In. The. Basement. I have replaced two already due to rust and leaks, why work to replace another 30 or so? Better to just rip it all out, run PEX lines, and forget about it for another 20 years. I have small windows between tenants to do bigger jobs, PEX seems like a good way to upgrade and make life easier down the road.