We have a very large 6 pane window system in our bedroom. These windows have been problematic since we bought this house. These windows are roughly 30" square making a 5' high window. (Double or stacked row).

The problem we are having is the level of condensation which is destroying the wood casings & trim. I've just replace three of the sealed units which still sweat with the approaching cooler weather.

The factors I see causing this are;

1 - The blinds we close over these windows cause the most trouble. We never close the curtains over any other windows in the house (There are two more sets of these huge windows) and never have the same problems. If we leave the blinds open all day they stay clear.

2 - This room has only one floor vent, and is at the end of a long hall. It is the coldest room in the house. Especially when the door is closed all day. (Pets and kids) - Very little airflow.

I was thinking of mounting or projecting the blinds 3-4" away from the wall, so the air from the floor register can pass over them. If I have to, I'll concider adding a long electric baseboard heater underneath.

Any thoughts?

 

You are on the right track.

Condensation is a result of air sitting avainst the panes, permitting condensation. - Moving the blinds out is not the only solution, but the circulation within the room and the whole house is very important.

Your humidity is too high for the room temperature.

DYou said you have one "vent". I assume you mean supply. Do you have adequate returns in the room to permit the proper flow of air in the room? Rooms on the end of a run are usually colder, which reduces the temperature of the air in contact with the glass, casing condensation. Air cannot hold moisture when it gets cool, so it is easy to create condensation.

Keep in mind that a window is a hole in a wall and nothing in terms of extra panels, gases will not make a real apprciable difference compared to the wall. You are just making something bad a little less bad. You would not have condensation without windows, but they are needed. Stale/uncirculated air can hold more moisture and will make condensation easier.

Dick

 

Thanks Dick, one supply vent is correct. There is 2 cold air returns in the room, but our furnace isn't one that circulates air at a low speed when not calling for heat. (I wish I had my time back on that one...would have opted for a better one)

I just put in a ceiling fan that we will try running on low speed for the season. maybe that will help too.

 

Reducing RH will solve they window condensation.