4 posts / 0 new
Last post
Dana
Condensation on Windows
Dana

Hello, I am at my wit's end trying to figure out the condensation on my windows. My house was built in 1940 but has double paned replacement windows. The condensation gets so bad that I am wiping puddles of water off the window sills. The condensation lasts all winter and is driving me crazy. Any ideas of how to improve it?

Other information that may or may not be important:

  • The house is balloon framing.
  • I just added more insulation to the attic but the condensation is still forming. 
  • It is a small, 832 square foot house. 
ordjen
Re: Condensation on Windows
ordjen

Obviously, the humidity is too high in your house. The question is where it is coming from? You might want to get a humidity meter to see how high the humidity actually is. Between 30 and 40% relative huidity would be in the  normal range.

Questions I would ask:

- What kind of heat do you have? Central heating systems that don't use outside air for combustion help evacuate excess humidity and send it up the  chimney. Newer high efficiency furnaces don't, trapping moisture in the house.

- What are your showering, cooking and laundry habits? Do you have adequate exhaust fan ventilation to get rid of the moisture these activities generate.

- What kind of foundation does your house have? Are you on a crawl space? Does that crawl space have a plastic vapor barrier on the ground?

You have to identify the source of the moisture and eliminate or lessen it.

TOHFan
Re: Condensation on Windows
TOHFan

I have a newer home with an air exchanger and still had some condensation problem at the bottom of some of my window panes on the inside. I started leaving a 2-3" gap between the bottom of my window blinds and the sill. This allowed the warm air to circulate better over the window pane thourgh the gap. I no longer have condensation. I don't know if this will work in your situation though. Like ordjen suggested, I keep a humidity meter to check on relative humidity level. These are inexpensive (under $10).

ordjen
Re: Condensation on Windows
ordjen

This is one of the main reasons that in homes with hot air heating systems, the vents are always laced under the windows. Air movement, especially heated air, always reduces condensation. In hydronic systems, the perimeter outside walls, with their windows,  always have the radiators.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.