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Tbone1128
Condensation on new windows

I recently installed new windows in my town house. I noticed condensation forming on the inside of the windows throughout the night. I am trying to figure out why and how to stop it. They do not appear to be drafty, so I dont understand if I am getting cold air leaking in? Any thoughts would be great!

canuk
Re: Condensation on new windows

Check the Relative Humidity (RH) level in your home.
If it's high this will condense on the colder window surface especially during the night when outside temps drops.

Tbone1128
Re: Condensation on new windows

I have a portable humidifier that states the humidity is in the low 70's.... Not sure what to do with that. Thanks for the reply.

inspector joe
Re: Condensation on new windows

The usual culprit is excess humidity in the home. Perhaps the older leaky windows allowed some of this humidity to escape. Or maybe the timing of the replacement. Is it much colder now after the windows were installed than before? For example, I see occasions of condensation on the interior of windows in bedrooms (sleeping people give off lots of water vapor especially with the doors closed), bathrooms (is there a vent fan and does it exhaust air to the exterior of the house, not the attic?), gas fireplaces give off water vapor, recent precipitation, etc. Check these things. Good luck

canuk
Re: Condensation on new windows
Tbone1128 wrote:

I have a portable humidifier that states the humidity is in the low 70's.... Not sure what to do with that. Thanks for the reply.

Yikes ------- that'll do it -------- way too high not only with condensation issues but could create an unhealthy envioroment for mold and mildew in the home.
50 % is plenty.

If you are using the humidifier -----cut down or stop using it.
Run bathroom and kitchen exhaust fans often and regularly providing they exhaust out doors, to helps reduce the RH.

The colder the outside temps the lower the inside RH should be inside to prevent condensation on the windows.

The condensation on windows is an indicator of too high RH.

Tbone1128
Re: Condensation on new windows

Thanks gents -

I dont run the humidifier anymore, I had it plugged in so I could get a reading, not too sure how accurate it is though. The windows have been in since the summer and the condensation definitly goes with the colder outside temps. I notice it is worse in the bedrooms in the morning, then any other rooms. The bathroom fan exhausts to the outside so I will try running that each day to help get the humidity down. Thanks for your help.

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