Sweaty walls - Is it the steam heater?

Jguerrero

Hello all. I live in a co-op apt built in the 1950s. We have two steam heaters under windows inside the walls, in the living room and bedroom. During the cold winter days, several exterior facing walls are drenched and dripping as well as the windows and the area surrounding the windows. Even in the kitchen where there is no heater; the kitchen ceiling even gets wet.  The mgmt office blames the windows which are from the 50s. What are the chances this will stop when we get new windows which will in sometime this year? Is the problem excessive moisture and zero ventilation? Not sure if theres something wrong with the heaters themselves, also ancient. Please help!

nicholas bonham-carter

Can you hear any steam escaping from the radiators under the windows? Is there moisture collecting on the covers?
Generally the outside air in the winter is drier, and air leaks through the windows make the humidity lower.
What other sources of moisture are in the apt?—NBC

Jguerrero

Oh, i guess once we have the new windows we wont have as much infiltration. I was wondering if it could also be poor insulation on the exterior walls. Going to buy a dehumidifier, thanks. Do you suggest one in each room?

Jguerrero

Hi nick, we do hear some noises from the heater but im not sure if its steam escaping. There is no moisture collecting on the covers for the heater, just some orange rustiness which scrubs off.  No other sources of moisture that we are aware of.

Jamie Hall

If the relative humidity in the space is high, and there is little or no insulation, you are going to have wet walls. And the relative humidity may well be high, just from living in there. Happens with pretty much any heat source, if you don't have enough air exchange.

AdmiralYoda

For that to happen you need ALOT of moisture, or a good amount of moisture and uninsulated walls. I lived in a 1800's uninsulated two family for a couple years. Every time we started a batch of homemade soup or pasta sauce and simmered it all day.....the walls would sweat in the winter.

Do you have access to the basement? If so is the boiler maintained and updated? Who adds makeup water to the boiler....is there an automatic water adder? Do the radiators leak or hiss steam at all?

I steam system in good operation is silent and doesn't leak a drop. Water will hardly needed to be added to the boiler.

neilc

I'm gonna disagree with YoungPlumber a little,
if it was air infiltration you would have dry winter air, and no humidity,
this sounds like the steam vents, or valve stems, or broken pipe, is leaking steam.
do you have working bathroom exhaust fan?
in the end, No, the Apartment should not be dripping.

Jguerrero

No vents at all, the building does not allow it. The basement access if only for the laundry room, not sure where the boiler is held or how its maintained. Actually, the bedroom heater has a dry streak of orange running down the front and left an orange mark on the wood floor, must be leaking water. I guess the real problem is the heaters themselves. I’ll try to get the office to repair or replace them but its an uphill battle. Thank you all for the help

bburd

Excessive indoor moisture can sometimes be caused by a gas burning appliance that is not vented properly to the outdoors, like a boiler, water heater or clothes dryer. Sometimes problems occur in the venting, even if the appliance was properly installed.

If there are gas appliances in the building, you need a working carbon monoxide detector in your apartment. 

Jguerrero

Mirror trick, good idea. Will try that. We dont have any appliances other than the stove/fridge. Going to record the noises, try the mirror and call my super in here tomorrow. Wish me luck, thanks guys. 

AdmiralYoda

Let's say it's a typical winter patter with temps below freezing.  In my now insulated 1899 house I have problems with the air being too dry!  The indoor humidity has been 9-15% lately.

Moisture is coming from somewhere...that much moist outside air would take a pretty strong draft and it would be obvious where it was coming from.

After that the occupants are making it by simmering water all the time or leaving the shower running.....or the steam system is leaking it.

Jguerrero

Held a mirror to the heater vent and it fogged up. I just realized the heater in the bathroom never makes a peep. The other two must both be leaking.

EBEBRATT-Ed

Moisture condensing on cold walls=poor wall insulation walls are cold and they should be on the warm side of the insulation

and moisture inside the building from cooking, showers and /or steam leaks

The Steam Whisperer

Typical winter Outdoor air when warmed to 70F has a very low relative humidity.... around 15% most of the time. When I have someone with a very dry house, the first thing I tell them to address is excessive air leakage. Insulation has little effect on air leakage. Reducing air leakage brings in less dry air, increasing the relative humidity since the moisture from people, bathing and cooking stay in the building longer. If your windows are very leaky, it sounds like you have steam leaks.

nicholas bonham-carter

Good quality combination storm windows may be just as effective as low quality replacement windows.—nbc

The Steam Whisperer

Usually more so....they last way longer.

Jguerrero

Hi - this is the third winter here but first time with this issue. No vents in the kitchen or bathroom because the building doesnt allow them. Actually the super came by this morning and changed the valve on the heater which had cracked. Much better now! I cant believe the difference. Windows are bone dry and i dont feel humid like before. Most importantly we can finally keep the windows closed! Im in NJ and we just had a big snow storm, its freezing out. Thanks all