My water service is copper and is not sleeved or wrapped where it enters my basement foundation. Its been like this for decades.

Is this something to be concerned about?

Thinking back of previous old places I have lived, I have never seen a sleeved pipe. Is this a regional thing? Or a more recent code requirement?

I am not a plumber but I had always seen copper pipes at manifolds coming up through concrete slab sleeved down here in South Florida. The reason I was told by several plumbers is if you don't there will be chemical reaction between the lime in the concrete and the copper and corrosion would occur.

However, I found a reference in an article by The Copper Institute COPPER.ORG that claims (and The Portland Cement Association backed them up) that there is NO corrosion concern between copper and wet or dry concrete. The sleeve is done to provide space for thermal expansion and abrasion from movement.

Here is the article:

"It is completely acceptable to bury/embed both hard drawn and annealed copper water tube in concrete. Decades of satisfactory service experience with the use of copper tube for in-floor radiant heating systems, water distribution systems and snow melting systems attest to the compatibility of copper tube embedded, encased or in contact with concrete

The copper tube must be completely embedded in the concrete and adequate provision for thermal expansion should be provided where the tube enters/exits the concrete.

It is also acceptable to run a copper water tube through a concrete floor or wall, provided that allowance is made for the lateral thermal expansion and movement of the tube and protection of the tube from abrasion. This can be done by insulating the tube where it passes through the wall or by wrapping the tube with an approved tape (to avoid abrasion) and installing it through a sleeve. Please refer to your local plumbing code for specific requirements regarding the protection of pipes and tubes passing through concrete and masonry floors and walls.

Both of the protection methods outlined above and the requirements listed in most plumbing codes are simply to protect the copper tube from the fatigue and wear caused by thermal expansion and movement. These protective measures are in no way dictated by the interaction of the concrete and the copper tube.

According to the Portland Cement Association the interaction of copper with both dry and wet concrete should not cause a corrosion concern. However, copper should be protected when it comes in contact with concrete mixtures that contain components high in sulfur, such as cinders and fly-ash, which can create an acid that is highly corrosive to most metals including copper.

A screened soil/pulverized limestone mixture is recommended as a selective backfill for copper tube to help eliminate corrosion concerns."

Here is the link: [www.copper.org]

If you go to the link it has additional articles and technical bulletins in PDFs.