Natural gas line: CSST flex pipe or black iron pipe?
March 4, 2017 5:32 PM   Subscribe

I'm in the process of installing a long natural gas line in my mid-19th century rowhouse. It will run about 45 feet (inside the house) from the gas meter in the basement all the way to the attic. It appears that I have two options - CSST flex pipe or black iron pipe. Help?

Reading up on this topic, it seems that I have a choice of CSST flex pipe or black iron pipe - CSST apparently being newer, with questions about its durability during lightning storms (and at other times?); and black iron pipe apparently being the tried and true option. I've done a few hours' reading on Google, but I'd be interested to hear thoughts of those more informed than I am on the subject.
posted by ClaireBear to Home & Garden (6 answers total)
Black iron is basically impervious to damage. It is also much more expensive to install; especially in a renovation/retrofit situation.

Personally I wouldn't bury CSST in a wall where it can't been seen (even though it is legal to do so, at least where I live) as I've seen way too many concealed water pipes and electrical cables damaged by nails/screws and that strikes me as more exciting than I'd like when it comes to gas. Though practically all new construction uses a flexible pipe (either CSST or Copper) with anecdotally few problems.

PS: if this is DIY the fittings you can buy at home improvement borgs tend to be low quality; a supply house (if they'll deal with you) will have better material.
posted by Mitheral at 7:16 PM on March 4, 2017 [1 favorite]

Thanks, Mitheral! Just to clarify, this is definitely not DIY. I've had around 15 price estimates from plumbers for the job, and they're all across the board in terms of price. The black iron estimates are typically higher, although some of the CSST ones are just as high.

I gather that the black iron piping has more joints where presumably leaks could happen - would you say this is a significant concern? Is cost the only disadvantage of black iron pipe vs CSST?
posted by ClaireBear at 7:33 PM on March 4, 2017

Also to clarify: the gas pipe will be exposed for now (in the sense that it's being installed in the corner of a niche along the wall) but the plan is to build a built-in bookcase with wide decorative molding disguising a hidden side compartment that opens to reveal the pipe, so it's easily accessible for maintenance.
posted by ClaireBear at 7:36 PM on March 4, 2017 [1 favorite]

Black iron is the fool-proof old solid standard. It's expensive in terms of labor but if installed properly and it passes its first pressure test it'll almost certainly last forever (especially indoors). The reason to go with CSST is that it takes a ton less labor and skill so is a lot cheaper; it is, however, less proven in the long run. Caveat emptor.
posted by introp at 8:16 AM on March 5, 2017

I bought my 1920's house after it had had a pretty good fire in it and rebuilt it. The original black iron gas lines were not affected. Neither were the original galvanized iron water pipes.
posted by rudd135 at 12:54 PM on March 5, 2017

In case anyone ever reads this question later, I wanted to follow-up to say that I decided on the black iron pipe over the CSST. From my research, and from the answers here, it seems like far more of a known quantity, and the channeling of an explosive through my house is not an area in which I'm inclined to take risks. CSST is probably fine, but I'm not going to be the one to find out. The bids for black iron pipe were largely pricier, although not uniformly so, and at the moment it looks like I will be going with a master plumber who will do it in black iron for under $1000 (although most of the bids were several times this). My biggest tip to others in my situation is to get as many estimates as possible, as the ones that I got were really bizarrely varied in terms of price.
posted by ClaireBear at 3:39 PM on March 21, 2017

« Older What movies are about cultures interacting?   |   Best caching behavior for various streaming sticks... Newer »
This thread is closed to new comments.