Condensation on windows

[John]

Hello.

I use a humidifier at home especially at the moment in Winter because the humidity is too low, and it helps my skin.

It causes a lot of condensation though on the windows. Is there any way I can prevent condensation without turning off the humidifier?

I have the temperature of my room around 21c and the humidity between

50% and 60% RM (this is comfortable for me and helps my skin). Without the humidifier it is only at levels between 25% and 38% RM which is a really low level and causes irritation.

Thanks for any help with this.

John

[kjpro]

Buy better windows!

[New Directions In Building Ser]

The condensation is caused by the glass surface temperature being less than the dew-point of the room air. In your case this is about 15c~16c. Therefore the only way to not have the condensation is to elevate the window surface temperature above 16C Try double or triple glazing or fit a small heater immediately under the window (inside) or low volt demister strips like car rear windows.

[Greg O]

50-60% is awfully high. Can you tolerate lower humidity? 40% perhaps? I would be concerned of mold growing in hidden places of your home with high humidity, Greg

[Dale Farmer]

Retrofit with better insulated windows. Double or triple glazed. Even if you can only afford to replace a couple each year, do it. Until then, you can buy those plastic shrink wrap kits to put inside of your windows to provide better insulation.

--Dale

[New Directions In Building Ser]

Greg,

45%~65%RH is the preferred comfort range by ASHRE 55 and ISO7730 (environmental comfort standards). Mold growth is usually not elevated unless the RH exceeds 70% for extensive periods. However at 65% and above, I'd suggest at least a weekly wipe over with a low grade biocide on horizontal surfaces and a thorough periodic clean for good housekeeping. Mold growth in non tropical areas is usually the result of something going wrong eg. leaking roof, leaking pipe, deficient waste removal, deficient cleaning, etc.

[Greg O]

North Dakota must be tropical area then. Greg

[stretch]

Just because the RH is 60% in the room does not mean it is 60% everywhere in the house. If the inside of the exterior walls are cold, the infiltration through the walls can take the moisture from house into the walls. The cold temoeratures there can cause localized condensation or RH above 80%. There is potential for mold growth under these circumstances. I have seen it happen. I would turn the humidity setting down, depending on how cold it gets outside. Stop the window condensation and the walls will probably be safe.

Stretch

[grom-it]

On small boats the windsheilds and portholes have their condensation reduced by rubbing a bar of soap over the surface of the glass...