How do I determine the humidity level in my home?

[Amitayus]

I am trying to solve a dust problem and am considering a whole house dehumidifier. I don't have musty odors, sweating windows, or mold.

How can I determine, though some sort of measuring device, the relative humidity, and if I need a dehumidifier or a humidifier?

[dlove]

http://www.amazon.com/Acu-Rite-Indoo.../dp/B0013BKDO8

the recommended indoor RH is 30 to 50% depending on the season

[Amitayus]

http://www.amazon.com/Acu-Rite-Indoo.../dp/B0013BKDO8

the recommended indoor RH is 30 to 50% depending on the season

Thank you. I just got something similar. I am monitoring the RH with a digital weather station. It has been staying around 50% the past few days.

[darkbeekeeper]

Have your building envelope checked more than likely you have a duct leakage problem,or to much outside air coming in or you just need better air filtration if it is bad have a blower test done along with a duct leakage test it will answer a Bunch of questions find problems the home will be more comfortable and the by product of finding and fixing the problems you will more than likely save on your elec gas bill air sealing and insulation is cheap

[Boh]

I live in Saskatchewan and generally I try to keep it less then 60%RH in summer months by running my dehumidifer and/or central air. Dust mites and mould tend to thrive in conditions higher than 60%RH.

Winter here is very tricky on account it hits -35 Celsius on a regular basis. 30% RH would be ideal, but even with new windows, I will get condensation. So 15-20%RH is usually where I keep it. I use a whole house humidifier set according to O/S temp and if temp really drops and it is too humid, I turn off the humidifier and I run my hrv on high for a few hours.

According to CMHC, we generally don't need humidifiers in Canada... I agree, it can be hard on the skin and nose when RH is low, but it won't really cause major damage. On the other hand, too high RH can cause a whole host of problems! Use with care!


Boh

[daveknapp]

Thank you. I just got something similar. I am monitoring the RH with a digital weather station. It has been staying around 50% the past few days.

I wouldn't trust any of those digital humidistats, nor the analogue kind that uses a needle to show the humidity. They're very inaccurate, they could be off by 20%. They'll tell you when the humidity is going up or down, but that's about all I'd trust them.

If you really want to know the humidity level, get a wet-dry bulb thermometer.

That said, you probably don't need to know the exact humidity. A rough estimate may be okay, in which case a digital meter may be fine. Even if it reads 50% when it's really 30%, at least you can use it as a base to know whether or not it's too dry.

[BMartin9000]

A dial hygrometer is a pretty good way to measure the humidity.

[evanseabrook]

I'm not really sure how to approach this problem, my humidifier control shows my RH in the house is around 30% but the dial on my HRV control clicks in at around 60% RH. I live in Saskatchewan, Canada and the outside temp is hovering between 0C and -15C. I'm going to go out and get a hygrometer so I can get an idea which control is out, but I'm not sure what I should do after that? Is it possible to calibrate these controllers (I know, I didn't give any deal which controllers/units I have but I'm at work and don't have access to that right now). The controller for my HRV has 4 modes (off, constant, intermittent and circulate) and a dial for the RH. My humidifier only has a dial for the RH. I doubt these are set correctly and don't really understand the logic if one fighting another, etc. I have my humidifier set to 30% (it hasn't ever cut in IIFC) and the HRV doesn't ever run unless I set it to something other than off, but I'm not really sure where the RH dial comes in on the HRV controller. Thoughts?

[teddy bear]

I'm not really sure how to approach this problem, my humidifier control shows my RH in the house is around 30% but the dial on my HRV control clicks in at around 60% RH. I live in Saskatchewan, Canada and the outside temp is hovering between 0C and -15C. I'm going to go out and get a hygrometer so I can get an idea which control is out, but I'm not sure what I should do after that? Is it possible to calibrate these controllers (I know, I didn't give any deal which controllers/units I have but I'm at work and don't have access to that right now). The controller for my HRV has 4 modes (off, constant, intermittent and circulate) and a dial for the RH. My humidifier only has a dial for the RH. I doubt these are set correctly and don't really understand the logic if one fighting another, etc. I have my humidifier set to 30% (it hasn't ever cut in IIFC) and the HRV doesn't ever run unless I set it to something other than off, but I'm not really sure where the RH dial comes in on the HRV controller. Thoughts?

A cup with wet salt in zip lock plastic bag generates 75%RH. Put your meter in the bag with the cup for a couple hours.
Regards TB