Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

oil tank leg floor flange question

ron Member Posts: 229
i'm having a typical vertical steel 275 oil tank replaced, which sits in my garage on concrete. The existing tank has the 4 pole legs sitting on the concrete, and the concrete looks fine around it best i can tell.

my questions regarding the new tank which is the same as the old, will have new legs.
- Are the tank legs any different than the regular old 1.25" black iron pipe sold at the stores?
- i was thinking of using floor flanges on the bottom of the new legs, so they would not dig into the concrete. Instead the weight of tank with oil around 2000 lbs being spread out over the floor flange. I would get the new pipe legs cut to size and threaded, and then screw on the floor flange. any problems doing it this way, like the floor flange cracking over time?



  • kcopp
    kcopp Member Posts: 4,009
    Not sure where you are.... here is New Hampshire we are required to do a few things.
    Legs are 1.25"(typical) no more than 12" long,& must have flanges.
    Oil fill and vent at least 1.25".
    Oil line must be coated.
  • ron
    ron Member Posts: 229
    edited May 2015
    in CT. i have not looked in newly built houses within the last year or two, but have not seen any oil tank in houses 2005'ish and older where the oil tank legs are not just the straight pipe. I've never seen floor flanges used except in pictures on the web.

    is there a special floor flange, or is the floor flange sold off the shelf at depot/lowes fine?

    the other thing is i got an "oil tank leg set" from home depot and you can look it up online. those 1.25" pipes are threaded only at one end to go into the tank bracket. there's no way a threaded floor flange can go onto them... i was quite disappointed in the "tank leg set" being just 4 pieces of pipe only threaded at one end :(
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    On a good typical concrete floor it really doesn't matter flange or not. Just a nice touch. If you want them get 1 1/4 4 bolt flanges and 10 or 12" 1 1/4 nips.
  • Kakashi
    Kakashi Member Posts: 88
    They are cheap so I would use them. I don't think it's code where I live but, they spread the weight of the tank out and they help level the tank.
  • billtwocase
    billtwocase Member Posts: 2,385
    Flanges are not code here, but common sense to not use a nipple for them that are threaded on both ends, as it thins the steel. Never seen anything issues other than an outline where the tank leg was in contact with the cement
  • ron
    ron Member Posts: 229
    when you say don't have threaded at both ends,
    then for the floor flange where do you get those that are not threaded?
  • billtwocase
    billtwocase Member Posts: 2,385
    Tank legs are available that have only one end threaded. You can only use them if you are not going to use a flange. They are usually 12" long, but one can always make their own, as I have cut some material off to come up with my level and pitch. Unfortunately, cement floors are not level