|Posted on Friday, July 02, 2004 - 09:27 am: |
For an environment such a Chicago, New Yor, Detroit or Pittsburgh - is it appropriate to specify a 304 stainless steel for and exterior application? Under what circumstances or for what reason would a 304 continue to show rust time and time after "proper" cleaning?
Post Number: 117
|Posted on Friday, July 02, 2004 - 09:50 am: |
Check out the information on this web site:
|Richard L Matteo|
Post Number: 28
|Posted on Friday, July 02, 2004 - 11:20 am: |
Also check out the evaluations section in MasterSpec under Section 05500.
Type 304 S.S. is for normal use. Type 316 is for more corrosive environments.
Post Number: 118
|Posted on Friday, July 02, 2004 - 06:07 pm: |
The other thought that occurs to me upon re-reading the original post is that New York is different from Chicago, Detroit or Pittsburgh in that it has salt water to contend with because it's on the ocean, unlike the other environments. 304 might be fine there, but I think I'd seriously investigate 316 for New York.
|David Axt, AIA, CCS, CSI
Post Number: 287
|Posted on Friday, July 02, 2004 - 06:23 pm: |
Type 304 stainless steel will lightly surface rust in a salt water environment. The rust is cosmetic and can be easily buffed out with steel wool. Type 316 is more expensive due to the higher nickel content of the steel. Type 416 is also not available in may applications.
|Richard L Matteo|
Post Number: 30
|Posted on Friday, July 02, 2004 - 07:08 pm: |
It would also depend on what type of maintenance will be performed by the end user - if any.
Type 304 is probably okay for most environments if inland from water. Remember, Chicago, Detroit, and Pittsburgh are also on lakes or rivers. It doesn't have to be salt water.
If the surfaces can and will be cleaned regularly, I'd say 304 is alright.
If you are near the water, or there is little chance of regular maintenance, you'd be better off spending the extra for 316 up front so it won't look "dingy" later on. There is also acid rain to consider.
|Kenneth C. Crocco
Post Number: 6
|Posted on Tuesday, July 20, 2004 - 02:00 pm: |
Its not just the environment and the degree of maintenance. One should also consider the finish. If the finish is a no. 4 of similar there will be more corrosion than a no. 7 will have. Chicago should use 316, exterior, no. 4 finish where there is little maintenance.
|John Bunzick, CCS, CCCA
Post Number: 242
|Posted on Wednesday, July 21, 2004 - 09:29 am: |
The "T" (our public transit system) here in Boston completed a new station about three years ago. It's not open yet because the new line it serves is not completed. This stop is about 100 yards from the harbor (and only about 200 from our brand spanking new convention center). It has an exposed structural system of stainless steel, which is already showing the surface rusting described by David. Sounds like it's type 304, and I bet the T's maintenance staff will not do any maintenance on it. (What public agency ever has money for that? Plus, I'm sure they expected that with stainless steel, they'd never have to do anything.)