depending on construction between floors, it is possible that the humidity will "travel" through the floors to humidify the whole house. If there is plastic or other vapor barrier between the 2 floors it will only be able to migrate up stairwells, ect.

I have no jobs out there to prove or disprove this theory, but i have been told that walls and ceilings will not stop humidity, unless there is a vapor barrier.

If I am off base on my assumptions, believe me someone will be piping up to correct me

(At least I hope they will)

 

.....
If I am off base on my assumptions, believe me someone will be piping up to correct me ......

Stop that. No one on this board will jump in and dispute something said as long as your in the "brotherhood". I think.

While the humidity will eventualy increase throughout the house, the 1st floor unit may not run often enough to add enough humidity to improve the entire house.

I have the same situation. A/H in attic and need humidity. I'm waiting for Honeywell's Tru-Steam. If it works as advertised it should be the answer for this situation.

 

Absolutely. If you've ever watched clouds move throught he sky, then you've seen mositure in action. In fact, you could humidify just one room and it would have the whole house within less than 1% difference from the room with the humidifier in it. Pediatricians know this isse well and when a kid needs a vaporizor, the second thing they tell the parent after telling them to turn on a good vaporizer is to close the bedroom door. If you don't close the bedroom door, the vaporizer is trying to do the whole house and it won't give the extreme moisture the child's body needs.

 

hunidity will seek its own level and will go through wall and floors to an extent

depending on the run time of the first floor unit
keep in mind the second floor may or will also fight this affect

have you thought about a remote humidifier install

this is went the humidifier is installed in a closet and ducts ran to it from the furnace. best if located near a water line access

this works quite well when freesing is a concern

 

wow thanks for the great feedback. I was told about the remote unit for the 2nd floor but it would be installed in a closet with the vent "through the wall" to the hallway. (but the wife wasn't excited about punching holes through a bathroom vanity to get to a water supply).

From what you guys have said i believe the humidity will reach the 2nd floor so right now i just have to figure out if the basement furnace will run enough OR put a remote unit in the basement to blow into the first floor. (i think i can get a vent from the basement to the 1st floor). I wish i knew how much the furnace needs to run to keep the house at a comfortable RH. (or more importantly how quickly the RH leaves the house when not running).

thanks for the great feedback guys.

 

Why do most American homes need humidification in winter?

Is it because the furnace or heat source "dries out" the air?

No.

It is because most American homes are leaky, even newer construction. Outdoor air is extremely dry in winter, because cold air can't hold as much moisture as warmer air. Air is constantly leaking into a house from outside, drying it out.

Oh, you might say, I just saw the weather report where it was 35 degrees and 80% relative humidity outside. How can air that damp actually dry out my house? Here's how: take that same air from outside, let it enter your house, and then warm up to room temperature, without adding any moisture to it. What happens to the relative humidity level? Well, if your room temperature is normally around 70 degrees, the relative humidity of that air that leaked into your house and then warmed up to 70 now drops to 22%! Most people would say that 22% relative humidty at 70 degrees is very dry air, and not all that comfortable.

Short answer: finding ways to tighten up a leaky house will help indoor humidity levels stay higher in winter, and lower in summer. A house must have air exchange to be healthy...just not too much air exchange, or it becomes unhealthy from a humidity standpoint, since low humidity may cause respiratory problems and high humidity encourages mold, mildew, and allegren growth.

You may still need a humidifier if you tighten up the house, but it will be easier to maintain decent humidity levels, and cost less to do it. With a humidifier you are paying for the energy to run it, the water for humidification, and cleaning costs as the unit loads up with deposits over its running life.

 

I have the same question as budman328 but for a different reason so the answer might be different. I have a 1930s Colonial one A/C unit (serving both floors) with the A/H in the attic and no furnace, just radiator heat so no central forced air curculation in the winter. With the A/H in the attic and no furnace, a humidifier on this system is not an option. Also, since there is on air ciruclation from forced air heat, there is a differential of about 4 or 5 degrees between the 1st floor and 2nd floor (heat rising). I am considering a through-wall humidifier (AprilAire 350/360) and the easiest location would be on the 1st floor, through the wall dividing the kitchen and living room at the rear of the house. Being a center hall colonial, the only stairs start at the front of the house. To complicate matters, my walls are an early form of drywall, with a layer of "mud" then skim coat of plaster, which I suspect will make it harder for humidity to get trhough.

Will the 1st floor through-wall humidifier work or should I consider a unit on the 2nd floor? Also, since heat rises, I would think the humid air would too, but humid air is heavier than dryer air so the humid air might stay on the first floor (absent some system to circulate 1st floor air to the 2nd floor).

Any thoughts would be greatly appreciated (we just can't keep up with the room humidifiers).

 

The big picture is longer run cycles on your down furnace (heat rises), & longer run cycles on your upstairs a/c (cool air falls). Do you have the large open foyer/loft/great room with high ceilings? If you only have a stairwell, I doubt it will make any difference in the upstairs. If there is a vapor barrier between floors (doubtfull) it will not make a difference. We routinely install large bypass humidifiers on the 1st floor only, with few complaints about upstairs humidity levels. The humidity will rise with the heat, just like heat is always looking for cooler air. You cannot go wrong with installing a humidifier on the downstairs system first. You can even entertain the idea of lowering the temperature a degree or two upstairs to cause longer run cycles on the downstairs system if you have the home with open design. Just do not install an atomizing humidifier, period.

 

I have the same problem as Jamespatrick4. I have same set up, with steam radiators. The covers have metal trays that rest directly on top of the radiators that we can add water to.
While this is better then nothing, a automatic system would be much better. I've considered adding a system to the 1st floor A/C and just running the blower a few times a day.

 

I have installed humidifiers on the first floor units with no problem on the second floor. Be 100% sure the humidifier you install has the capacity to do the whole home with the run times on the first floor unit. I have only installed the Elite steam units for this since they will provide large quantities of water to your home. (depends of sq. ft.) Good luck.

link.http://www.generalaire.com/humidifiers/elite.php