Are Compression or Soldered Joints Better?

Service life may be a little less with compression joints, but after 20 years of service, who's going to know or care which was the best. The big plus is the savings in labor costs. The materials may cost more, but labor costs are less. Bottom line: compression joints mean more profit and as a bonus, the compression joints can be repaired more easily than soldered joints.

I suspect part of the reason for the industry shift to compression joints, especially for potable water systems, may have something to do with the lead in the traditional solders used.

An interesting compression system that might fit into this discussion is the Cash-Acme "Shark-Bite" line. I haven't tried it yet, and don't know how well it works and lasts. Basically, valves and fittings have compression ends that can grip the standard sizes of copper, CPVC, PEX, and other tubing. The system goes together with a wrench, and can be taken apart later for repairs or changes. The valves and fittings cost a bit more, but anyone can assemble them, and there is no risk of a soldering torch scorching nearby surfaces. (I'm an old lead-free Silfos guy from refrigeration, but this rather new system looks pretty good.)

In a house that is constructed predominantly of timber, a good practice is to solder chunks of pipework together outdoors into sub-assemblies, and connect these lumps into the building systems using compression joints.

Blowlamps and timber buildings don't really mix......

Soldered copper joints are more durable than compression joints, but take more skill to create. No one should use leaded solder in potable water systems. Sharkbite fixtures work well, and seem to have good durability. The issue of cost may have more to do with quantity than quality. In a structure that requires 100 joints, it can be more economical to solder them, but but a quick labor absorbing repair may be more easily accomplished with a compression, MPT/FPT joint or sharkbite fitting.

I wonder if evaporative coolers are used in Idaho. What do you call that 1/4" od white plastic tubing that is typically used for these systems nowdays, instead of cu?

For repairs to existing cu lines, it is joined to existing cu tubing or brass fittings with the usual couplers or unions, but when connecting to itself, a hard plastic ferrule and a brass tube insert is used.

I'm guessing in this usage, compression fittings are much more advantageous.

Pesonally I prefer solder, but in some instances where it is not fesable to solder ,,i.e water in line, to close to flammable material , a compression fitting works out well.

Cost for sure is one item to look at. Most plumbers are paid quite well and a large job using solder joints would eat up a lot of bucks. On the other hand a typical 3/4 inch valve with compression fittings can cost up to 5 times more then one with sweat joints.

just an opinion

oilcan13

The cost of material can be passed on to the customer.

There are some times when we use the SharkBite type fitting when we would have difficulty draining down the system or if we have to have the water turned off for a very short period of time. SharkBite fittings are rated to 110+ p.s.i. and they are very reliable. They are more expensive to purchase but installation is simple and quick.

I had a hose hydrant that froze and had to replace it up in the rimjoist area where I didn't have much room and they worked great. It would have been very difficult to solder.

Our contractors also have a type of fitting that crimped on by a battery powered tool. I think they can use those on fittings up to 2" or so diameter .

Shark Bit fittings are the best. They work just like a snap tight pipe (for municiapal water systems) or a field lock gasket, execpt of course you can disconnect them unlike a compression coupling (you would have to replace the ring and nut). Solder joints/comp joints and the newest Shark Bit fittings all all rated above 85PSI the regulatory max in your home. If your doing it yourself and you have little experiance I would use the Shark Bite (I would use it either way), soldering takes skill (do you have it), and comps are easy to use but not as easy as the shark bites (they just push together). With a comp if you dont cut the end square the pipe will bend in the fitting but still work, with shark bite the fitting will not grab so you HAVE TO CUT THE END SQUARE!!!!!

Actually all systems work well. It's more of a toss up as to which to use. It's a question of cost vs convenience vs future expansion vs repair-ability.20 years ago I would use soldered joints. Today at 76, I would use the easiest way.

Each has its merits and some applications would demand one over the other on a case by case consideration. Either one if performed correctly would be fine. Either one if performed incorrectly would be equally unsuitable. Experience, thorough thinking, available resources and skill will determine which one to use.