What is the best alternative to galvanized steel pipes? Plastic or Copper?

I'm a commercial plumber, and isntall this stuff for a living so i'll give ya the low down on it. Copper is the best pipe for running water because it has a very low probability of ever breaking and last for your entire lifetime. Plastic pipe (pvc, cpvc) has a higher probability of bursting and flooding your house, and will probably need to be replaced sometime in your lifetime. Copper sounds great doesn't it? Well copper will cost you a lot more money than pvc. Most houses have pvc in them, its really only bad if it is run under a slab or put in incorectly, as long as you don't go with poly pipe, either one will sufice. Its really up to you on how much you want to spend.

I spent some time in front of the computer for some good information about PEX or copper, and I found this article here very useful: http://www.miconstruguia.com/en/how-to-install-pex... Hope this works for you too.

Copper is the better product of the 2 to use. If you install the pipes in your roof cavity, the heat will eventually make the plastic pipe brittle and it will have to be replaced or you will be flooded and then it will have to be replaced. The plastic pipe will be easier and cheaper to install but I can promise you that if your existing pipe were plastic, it wouldn't have lasted since 1912 till today. The plastic manufacturers will try and tell you their products will last longer than the copper, but how many of them will there be available to help you out when the house is flooded.

There is another product on the market which will install as easy as the plastic pipe and it has all the qualities of the copper pipe. I can't remember it's name now (even checked through my catalogs) but it is a spiral type steel/copper inner wrapped in a thin pvc layer. It bend at smaller angles than a plastic pipe and all fittings are crimped onto the pipe. It come in 100m rolls and you cut it with a type of "side cutter" to the correct length.

Plastic pipe is cheaper and easier to install (and you don't need to light a torch to connect it together). Copper is a stronger pipe and will provide a longer life for the new piping. Either of these choices will be an improvement to the galvanized pipe you currently have. You may want to look at putting copper in areas that are harder to get into, and areas exposed to the elements, where the extra strength may be helpfull. Then, use plastic pipe everywhere else.

Copper is the best but very expensive now. PVC is not allowed in all areas and I have not seen anywhere that allows PVC for hot water lines. It must be CPVC. The newest piping is PEX. It is easy to install, fairly cheap and can be snaked into areas where hard pipe would be difficult or impossible. The tool for installing PEX is expensive so you may want to rent it. Make sure it has been calibrated before taking it home.

CPVC (plastic) is by far easier to install and is less expensive (especially with the cost of metals right now). Personally, I prefer copper because it is more rigid.

If you go with a metal system, by code you need to ground the pipe to the electric system, a jumper (a wire) connecting the hot and cold pipes at the water heater, and a jumper at the water meter. The wire I have used for jumpers is #6 bare copper.

Copper is the best of the best. I will never rust. Though it is the most expensive. Plastic is weak and may cause problems down the road.... Galvanized is ok. I will last for MANY years.

What you have think of when choosing one is..Will I outlive the plumbing. is the value of the house going to encrease if I sell ..

plastic is cheaper. copper is better. beyond that, it's a matter of your skill level. anyone with a hacksaw can run plastic. copper will require the use of a torch, which can prove difficult and dangerous in a retro-fit, as you may be putting open flame close to combustibles inside existing wall cavities.

another option that you didn't mention, is crossed-link polyethylene, or PEX. it's a flexible tubing that is very easy to install.each fixture has it's own dedicated line, or home-run, coming from a manifold, so that there is no fittings except at each end. PEX can bend around corners without any elbows. the only thing is, you'll have to buy, or rent, the tool for making the connections.

Plastic is going to be the easiest to install. It's easier to cut, prep and glue together. It's lighter and everything about it is just plain easy but it's easier broken and frozen in winter if it's not properly insulated. Copper is more durable and a higher value should you try to resell your home but you have to sweat each piece together with solder.

If you want easy and quick go with PVC pipe and you'll have it done in no time.

Cheaper and easier would be pvc (plastic). Best would be copper. Many states do not even allow pvc pipe for domestic water use.