How bad is it to remove a steam riser that has no radiators?

bipbap

We need to do some structural work as part of a renovation and the critical spot for a steel beam is right where the steam riser is.
This riser comes up out of the basement and runs up through a bathroom closet on 1st floor, inside a wall on the 2nd floor and is exposed in the bathroom on the 3rd floor. So it's heat is only really felt on the 3rd floor.

There are no radiators connected off the riser at all, just one straight pipe up 3 floors. One of the tenants who's been there for 50 years says he never even recalls any radiators being attached to that riser.

So we could just move the whole riser over (which would be tricky since we are not doing work on the 2nd and 3rd floors) or we could just remove the whole thing. FWIW, the bathrooms are never that cold.

This is an unexpected potential cost to move the whole thing so I'd rather just remove it if it won't do any major unbalancing to our one-pipe steam system.

Any thoughts?
Thank you in advance!

Jamie Hall

Double check and make sure there's nothing at the top. Then... Sawzall time!

bipbap

What would be at the top to watch out for?
It does have a Gorton vent a foot below the 3rd floor ceiling mounted right on the riser and then the riser continues up above the top floor ceiling but I don't know how far up it goes into the ceiling.

KC_Jones

What other radiation is in this 3rd floor bathroom?

Jamie Hall

bipbap said:

What would be at the top to watch out for?
It does have a Gorton vent a foot below the 3rd floor ceiling mounted right on the riser and then the riser continues up above the top floor ceiling but I don't know how far up it goes into the ceiling.

Ah... oops. Don't even think about taking it out until you figure out where it goes in the ceiling. I assumed (silly me) that you could see the top end. And if you do find that it really truly dead ends, you may also find that you need that vent anyway. More research is indicated.

DanHolohan

Is that the heat for the 3rd-floor bathroom? That’s common in apartment buildings.

bipbap

Yes, it looks like it only provides heat for the 3rd floor bathroom at this point. That's the only room where it is exposed.
And there is no other heat in any bathrooms, other than an electric floor tile heater in the 2nd floor bathroom.

If there is a vent at the top of the riser, does that mean that vent is critical to the overall system and should remain?
The idea would be to just fully remove the riser down to the basement.
Just the cost of moving the whole thing is hard to handle a this point in the project.

DanHolohan

Yes, the top of the riser needs a vent for the riser to work as a radiator. If you remove the riser, how will you heat the bathroom?

Is this in NYC?

KC_Jones

If there is no other heat source that pipe is the radiator for that room, remove it and most likely the bathroom gets cold.

A bathroom is the last room you want cold, in fact most will agree you want that to be the warmest room in the house.

bipbap

Yes it is the heat for the bathroom, but the other 2 bathrooms have no heat from that pipe and they're fine. Plus, I plan to renovate that 3rd floor bathroom to add the tile heat mat which seems to give a good amount of heat in such a small bathroom.

And yes, Dan, this is in New York.

So if we said providing heat to the bathroom wasn't an issue, does it affect the overall system to remove it?

DanHolohan

Yes.

bipbap

Ok hmmm.
So what kinds of issue would that create?
Just trying to get past the potential cost of relocating the riser for all 3 floors.

DanHolohan

If you add the heat mat you'll probably be able to get rid of the riser. Make sure you size it properly.

KC_Jones

If you have tenants, have you asked code enforcement their thoughts on having unheated rooms in a rental property?

In my neck of the woods that's a big no no, I know FHA also has problems with that.

Not trying to cause you issues just making sure you don't cause yourself any issues.

bipbap

Dan, you said probably- do you have doubts about removing it?
Assuming I replace it with a new bathroom heat source.
Will it significantly screw with the rest of the system?

Steamhead

Radiant floor heat mats are problematic. If they stop working, you have to tear up the floor to fix them.

And in a bathroom, there is a lot of water. If one of these mats gets wet, it could pose a shock hazard.

Move the riser.

ratio

Maybe only the part of the riser in the way needs to be relocated? Then you're minimizing the work on the second floor and no change to the third.

It'd take someone who understands steam to make the change.

DanHolohan

It shouldn't affect any other part of the system if it's just a riser as you're describing it. It will just take away the heat in that bathroom.

bipbap

Ok that’s good to know.
I recall reading when removing a radiator it can’t throw things out of balance with the overla system but wasn’t sure if same held true for removing a riser with no rads attached.

DanHolohan

There's not much heating load on a riser like that.

bipbap

Ok also good to know.
And what usually do you find when a riser passes through into the top floor ceiling?
Is it just a capped end of pipe?
It’s hard to even tell how far up into the ceiling it goes.

DanHolohan

It would usually be capped.

nicholas bonham-carter

Hopefully it’s not a downfeed supply. Can you see what is above in the attic?—NBC

bipbap

I can’t see above.
What would I see if it’s a downfeed supply?

Fred

bipbap said:

I can’t see above.
What would I see if it’s a downfeed supply?

If you could see above the ceiling, you would see the pipe turn in some direction run a length, horizontally and drop back down to a radiator somewhere on the second or third floor. Is this a one pipe or two pipe system? If one pipe, there would be a drip for condensate somewhere near the radiator it feeds (but it could be under the floor and not visible at the radiator. If it's a two pipe system, the drain pipe on the radiator would carry the condensate back to the boiler.

bipbap

One pipe system.
There’s no radiator anywhere nearby so I kind of doubt it and the riser has no radiators connected at all.

Fred

bipbap said:

One pipe system.
There’s no radiator anywhere nearby so I kind of doubt it and the riser has no radiators connected at all.

It just seems strange, at least to me, that if that riser were a source of heat, just for the third floor bathroom and it is in a closet on the first and second floor and only exposed on the third floor, why wouldn't they have taken advantage of the small amount of heat output all the way up? Does it look like the first and second floor closets were added at some later date?