Hummidity

[Anonymous]

What is the average allowable or desireable hummidity level in a 3000 sq ft home say in the midwest.

Does 40% - 50% sound to high?

[Rich]

Here in Colorado I have a tough time keeping 50% R.H. in a small bedroom (will hit it once every couple days). Although it is quite a bit drier here than most places I've lived. I would say around 35-40% would be typical in winter conditions.

[oldfella]

35 to 50 sounds reasonable, for furniture and humans.

[Anonymous]

The problem is: windows sweating in an ICF concrete home

The homeowner does not have an "air exchanger" and runs a floor model dehumidifier. When he runs the machine, no sweating.

Several variables can be considered. We were just curious as to what other opinions might be about desirable humidity levels.

[Rich]

oic.. So your problem isn't that you have not enough humidity but that you have too much. I've never lived anyplace where that has been a problem.. haha. :lol:

I know for me at 30% RH my skin feels really dry.. at about 40% maintained RH it's alright but when I get up over 50% it seems to make me uncomfortable. What may seem normal for some areas may feel totally different in another depending on what the typical condition is.
Of course, that still doesn't help your windows from not sweating.. just you.

[Dano]

Depends on what or who? For Human comfort ASHRAE recommends between 30-60% which in my experience 45-60% is a good range. If you have alot of millwork in your home and or solid wood furniture....I would maintain on the higher end 45-55% to keep from shrinking especially at joints. If your going to control humidity..just be aware that your operating costs go up because humidity control supercedes space temperature control.

[grumpydasmurf]

Humidity can be destructive in the winter time around here. Condensation will wreak havoc on just about everything. Prepare for mold.



Come to think of it I've never lived in a house with a humidifier.

[roger g]

Gotta have a percentage of humidity like Dano said. If you have condensation you have too much humidity or it's where it shouldn't be.

Roger

[Rich]

I've had to do quite a bit of research in this lately to accomodate a very expensive collection of artwork and over a million dollars worth of millwork in the current project I'm working on. Is what I've been told from the wood and hvac experts is that for conditions in Colorado (which is pretty dry) is to keep humidity between 25% and 35%. Anyway - that's just what I've found in the last few months of looking into it.

[roger g]

If you are dealing with artwork and stuff I would go to a gallery and find out what they do. Same with record storage. What's good for art may be uncomfortable for living in.

Roger

[Rich]

In Colorado any humidity feels good :) less than 25% is detrimental to artwork - already have the presets and alarms setup in the BAS for that.

[mreynolds]

Check out this web site http://www.buildingscience.com/housesthatwork/default.htm. I just found it in the last issue of fine home building. If you click around they give information on how to construct building envelopes based on the region you lived (Check the bottom of the page for links). They spend a lot of time discussing vapor and which side it will dry to based on your location.

[Rich]

Some good stuff on there.. thanks mreynolds