Copper pipe touching pressure treated wood

Hi. We are in the process of having a deck built and have to decide on the type of railings to use. I would prefer not to use wood so I found some companies that sell galvanized aluminum rails in specific lengths but they corrode when touching pressure treated wood and have to have a special washer between the aluminum and the wood. We also wanted the ballusters to be horizontal between posts and thought copper pipe might be a good choice. I need help with the pros and cons of using copper. The pipe would be about 7 feet long between posts in 3 rows. Here are my questions:

What happens when copper touches PT wood?

What color does it turn when it has aged nicely?

Any idea on rough price for (roughly!) 250 feet of maybe 5/8" pipe? I live in Atlanta and am sure I can find it locally...

Any other info would be greatly appreciated!! Thanks!!

#1 I don't know

#2 Copper will turn brown & or green over time.

#3 250' of 1/2" copper will run you in the neighborhood of $500.00

I don't believe they make 5/8" copper pipe. It comes in 1/2" and 3/4", but not 5/8". Copper prices have gone through the roof in recent times so be prepared for a jolt. You should check with your local suppliers as to their current prices.

The old 'ID' versus 'OD' debate...

If someone is selling you galvanized aluminum rails he is an idiot or a faker. There is no such thing.

There is a product called Galvalume which is aluminum and zinc coating on steel. http://www.steelroofing.com/ The aluminum/zinc coating would also corrode when in contact with the copper in the treated wood.

If you are going to insert the pipes into wooden posts, you could easily isolate aluminum (say aluminum heavy-wall conduit) by putting a short piece of shrink tubing at each end where it enters the post. Aluminum forms an oxide coating and will not remain shiny.

Check with your code requirements. If the deck is more than 30" above the ground, you may need a railing that is at least 36" high and will not pass a 4" diameter ball at any place. Three horizontal rails won't pass that standard.

Seven ft long copper pipe will probably not pass the requirement to withstand 200 pounds at any point on the railing.

I think stainless steel costs about the same as copper now, and is a lot stronger. I have seen railings made with stanless cables. You need strong posts to withstand the tension.

Gary Swart said:

I don't believe they make 5/8" copper pipe. It comes in 1/2" and 3/4", but not 5/8". Copper prices have gone through the roof in recent times so be prepared for a jolt. You should check with your local suppliers as to their current prices.

Click to expand...

1/2 copper pipe is 5/8 outside diameter, 1/2 is the inside diameter.

tubing

Gary Swart said:

I don't believe they make 5/8" copper pipe. It comes in 1/2" and 3/4", but not 5/8". Copper prices have gone through the roof in recent times so be prepared for a jolt. You should check with your local suppliers as to their current prices.

Click to expand...

If you want 5/8" o.d., (1/2" i.d.) go to a plumbing store. If you want 5/8" i.d., (3/4" o.d.), go to a refrigeration supply company. But, 1/2" copper, even type "K" would be mostly cosmetic because it would not resist very much lateral force and would distort very easily.