insulating bathroom ceiling

Old 02-24-24, 02:13 PM
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insulating bathroom ceiling

I live in Vancouver, Canada. Not sure if that affects anything.

I own a 30-year-old one-bedroom apartment. The apartment has a bathroom with two doors: one sliding door that leads to the bedroom and a regular swinging door. The bathroom has no windows, and there is no apartment above mine. The bathroom also lacks a heater system.

I noticed that the bathroom humidity is high; the current value is 64%, which is high.

I wonder if I can insulate the ceiling and walls with pink fiberglass to reduce the humidity.
Thanks and have a good one.
Old 02-24-24, 02:20 PM
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Insulation will do nothing to change how humid a room will get. The best way to reduce humidity would be to install an exhaust fan to remove the humid air. Of course, when you run an exhaust fan the air has to be replaced so hopefully there is some type of makeup air.
Old 02-24-24, 02:43 PM
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Insulation would help the relative humidity "a little" *if* that insulation keeps the room warmer. Colder air basically concentrates the absolute humidity, because the ambient air temperature is closer to the dewpoint. Same exact air when warmed a few degrees will lower the relative humidity a few points. That's because warm air is capable of holding more moisture... therefore the RH goes down the warmer that same air gets. That is why the word "RELATIVE" humidity is used. It's directly proportional to the temperature and current dewpoint.

But yes, ventilation is the most effective way to lower the humidity by exhausting the humid air. This assumes of course that the makeup air has a lower humidity than what you are trying to exhaust. Example... opening a window near the bathroom on a cold rainy day would increase ventilation but would not lower the relative humidity, it would increase it. And technically all makeup air comes from outside, and if it is humid out, it must be conditioned to do much good. But in a bathroom it's usually sufficient to draw in air from another room in the house with lower humidity which is what happens when you turn on your bath fan.
Old 02-24-24, 03:35 PM
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The best option would be a vent fan but if that's not practical a small dehumidifier might do the job. Google small room dehumidifiers.
Old 02-25-24, 04:33 PM
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You need an exhaust fan. Any difference from insulation would be worth neither the hassle nor expense of installing it.

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