I live in a ten unit condo. The windows were replaced recently. They’re vinyl. My question is, should there be condensation on the inside of new vinyl windows? There almost constantly is.
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I replaced my single pane wooden sash windows with vinyl low E thermopane windows a couple of years ago . We had terrible condensation on the inside. Well we still got condensation,albiet not quite as much. Humidity ran around 50% due to numerous house plants,cooking,breathing,etc. and a pretty tight house. So I bought a dehumidifier and now the windows are clear. The windows stay clear below 40% humidity(depending on temperature) so its not like you have to run it all the time.
The old windows probably let in more air, and weren't as prone to condensation. The new windows are probably tighter. Drafty windows function a little bit like a defroster.
Mind saying whgether the condensation is on the vinyl or on the glass?
This question comes up on a weekly basis every winter. window people get the question daily, several times a day in the cold snaps.
Even with the best of windows, the glass surface is the coolest surface in a modern home. If your interior humidity is too high, the window is where you will see it.
A human is most comfortable at about 40% humidity. Unfortunately, that is where a house starts to develope moisture problems from condensation to mold. A house is much happier at <20% RH. work out your own balance with your personal environment.
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The condensation is primarily on the glass, but there is black mold growing on the vinyl of the windows that are condensating. Not all of the windows are condensating
Would I be right to presume that the ones that show condensation are on the north side ( coldest) and in rooms that naturally generate higher humidity such as bathrooms and kitchens? if so, thaaat testifys to the thought that your humidity is on the high side.Black "mold" spotting on the surfaces would typically be mildew, which needs food, moisture, and warmth to grow. The moisture is self explanatory, coming from the glass. The warmth is a good sign - that the frames of thesse vinyl windows has theraml breaks in that portion of the unit to keep it from being cold there. The food - usually dust particles in the air that settle on surfaces. Damp surfaces tend to hold the dust more than dry ones do. Using air filters in the home is healthier from otheer standpoints also and can reduce the dust that is feeding the mildew, ascan increasing the frequency of wiping down these surfaces with a mild detergente or household cleaning solution.
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I see a lot of this in the great white north! Are your windows dual or tri pane, slider, casement , picture, awning ? How much humidity ? Even the best windows will show condensation at very cold temps. (- 30 ) and at levels of 40 - 50 %. Open blinds to improve air flow around the window, lower humidity levels with dehumidifiers / exhaust fans or HRV & last , but the most important, check for combustion appliance back drafting / spilliage,as water vapor is a by product of combustion an you may have a furnace or water heater that is not venting properly! Hope this helps.
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I think I may be being too sensitive to the problem. After thinkiing on it I beleive my indoor humidity is too high. The condo is only 420 sq.ft. and the bath fan won't even hold a piece of toilet paper to it. I'm going to sic my dehumidifier on it.
Thanks for the info