Now that cold weather is here (10 degrees) I am again having trouble with ice and water on some of my windows. We have an open floor plan so I don’t understand why the thermopane windows at one end of the room are ok while the other side has a large buildup of ice and water. The windows are identical and go from floor almost to ceiling with forced air vents on the floor adjacent to the windows. We also have an addition that was added a few years ago with Pella thermopanes. This room does not get as much heat and is usually colder than the rest of the house. To try to keep this room warmer we recently added honeycomb blinds. Now the ice and water are so bad we have to mop up water several times a day. The humdity guage in the house reads between 35% and 40%. Any ideas whats happening.
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Unless the blinds can "seal" against the window frame they make the problem worse.
They act as insulators so that the inside of the glass gets colder, but enough moisture can still circuit around them (or maybe even through them) to condense on the glass.
I thought that was what was happening. Unfortunately with current gas prices we need to do something to reduce heat loss.
For your addition you may want to try those 3M transparent films which seal tight against the window. Since you have the honeycomb blind there I don't think the view is a problem.
so I don't understand why the thermopane windows at one end of the room are ok while the other side has a large buildup of ice and water
Does this happen day and night? The sun has anything to do with it? It could be the temperature difference from one side of the room to the other even though it is an open floor plan, or due te the difference in air circulation pattern.
It's cold out there, see what happens to my front door...
The frost has iced up and starting to melt, this is a clear indication that it is around 5F. I learned to read the outside temperature from the inside just by looking at the amount of frost on those bolts.
View is important as the addition looks out on a beautiful yard. I tried the film on the outside of a window a few years ago and the wind tore it off in a few weeks. On the inside it really spoils the looks of the room. I am thinking of trying to add a sheet of glass either inside or out but they are big windows (30x72 and 30x 80) and thats a lot of glass to store in the summer.
Your door looks like a big problem too. Have you had a problem with the finish?
The windows with the condensation are on the north side, right?
Or perhaps the other windows have bushes or evergreen trees "blockingb the view?
I'm thinking increased radiation from the windows with condensation and thus they get colder and thus have more condensation.
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In the main part of the house the windows that frost up are on the north side and with nothing near them. The windows on the other side face south and have a row of bushes about 4 ft away. The windows are about 30 ft apart and although there may be some differences in temp, it is not noticeable.
BTW - any window pane (storm windows) that are over about 9 sq ft in size should be safety glass. If storm windows are mounted on the outside, it would probably be less important, but if you look at the existing windows, I bet that there is a small faint stamp indicating some kind of impact resistance.Matt
Windowes facing north or towards open space will radiate out more heat than others, lowering the temp which can be enough for diffreneces in condensation.
That's the same principle as why your windshield will show frost first before your side windows - slanted up it radiates heat to the sky!
So the answer is simple - get more heat to those window surfaces!
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I'm matching tool donors to a church mission to Haiti - we're shipping a bus converted to a medical facility in (now it looks like) April and can fill it with clothes, tools and all sorts of stuff needed in that poorest of all countries. A few hand tools or power tools can provide a livelihood for an otherwise destitute family. Please email me if you have tools to donate.
Thanks to Jeff and David and Jim and Rich and Steven and Mark and Jason and Shep and Jen and Mike and Joe for their offers!
The first donation just arrived! Thanks and God bless!
Have your thermopane failed / defective? They do from time to time.
You need to find a way to drop the humid in your home.
Another is to keep a fan moving warm air over the windows.
Also magnetic storm window on the inside helps. Plastic film taped over the windows is alterative.
The ones that frost up are the coldest ones and/or it could have to do with hyow heat and air flows in your house. With hot air heat, the dry hot movement could be keeping some windows drier but not delivering much near the frosted ones.
A house is happier at 15-20% humidity while people are happier at 40%. 40% RH is the highest you should keep the house. Maybe try reducing the moisture level top 30% for a compromise if the window thing bothers you
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Thermopanes are all good (have replaced bad ones). I worry that if I lower the humidity to 20-30% the family will all start to have to have problems with their nasal passages. I have thought about running a dehumidifier in the addition but thats the same as cooling a room that I'm trying to keep warm. BTW the bedroom and bath windows are all single pane with storm windows and they don't have this problem.
Obviously, what is happening is when the warm air from the room hits the cold windows, the air temperature is reduced and moisture is given up. Relative humidity is relative to temperature. Cold air cannot hold as much moisture as warm air.
To add to what Piffin said, to reduce indoor relative humidity, an easy start is to be sure that anytime someone takes a bath or shower, the exhaust fan is used. Also, anytime a pot is put on the stove the exhaust fan should be used. Exhaust fans must move air to the out-of-doors. Check your dryer to be sure that the air exit pipe is not leaking. If you have a crawlspace or basement, check there for a moisture source. To check the basement slab, tape a 4 sq.ft. piece of plastic down on it and check it in a few days to see if moisture has formed on under side of the plastic. For a crawl space, it must have a plastic vapor barrier on the floor. Give these things a try to see if the problem is at least reduced.
Also, I agree with what Bob said about the problem windows being on the north side of the house, or otherwise are having the sun blocked from them.