Two handle to single handle tub faucet conversion

[Lee]

I am considering converting my two handle tub/shower setup to a single handle style. The 1/2 inch copper supply lines were joined to the old faucet via unions, thus I currently have threaded ends on both the hot and cold supplys. In the interest of an easy install, is there anything wrong with using some of those flexible copper lines (like are so popular in water heater installs) to just extend the supplys and turn the 90 to attach to the new single handle valve fittings? Are these even available in a 1/2 inch flavor? Is there some other acceptable threaded solution or is the "sweat" option the "hands-down" best way to do this job?

thanks,

Lee

[Speedy Jim]

I would never, ever use a flex in a concealed location.

A union is OK if they would help you preassemble the piping to the control. Better though is to sweat everything in place. (Remember to remove the "guts" of the control to avoid overheating it.

If you do use a torch inside the wall, place heat barriers around the work and wet down any studs, etc.

Jim