condensation on windows in new addition
Hello All,
we have had a serious condensation problem with our windows in our house, specifically in the new part of our home built in 2001. We have high end, double hung windows throughout, both in the older log part of our home and in the air tight newer portion.
What is hard to figure out is that the new windows in the older part of our home have hardly any condensation on colder days, while the windows in the new section of our home are almost coated with ice around the perimeter of the windows, especially on the 2nd floor.
Also, the newer addition was built with 2 X 6 exterior walls for added insulation value. On top of that, we added a 1 in. thick polyurethane foam sheets to the outside sheathing before putting on board & batten siding.
Any help in this matter would be appreciated.
Jeff.
Replies
My guess is the addition is tighter and the moisture is condensing just on the windows, unlike other, less tight areas where it is condensing on everything that has reached the dew point.
You have a humidity problem.
google: "Windows do not cause condensation"
Edited 12/20/2008 6:40 pm ET by sledgehammer
Edited 12/20/2008 6:43 pm ET by sledgehammer
thanks for all your replies & interest in our problem. It sounds like we have a humidity/ventilation problem. I will monitor humidity, especially in the newer/air tight part, and look into a small HRV, possibly, to improve things. We have wood burning inserts in the the older part of the house which I'm assuming is lowering humidity when we use them.I'm embarassed to admit that I haven't yet thrown down a vapour barrier on the ground in the crawlspace of the newer addition. I am sure that isn't helping our cause either. thanks again.
The condensation is due to moisture and the some common sources are:
1. Bathrooms. Those long, hot, showers generate lots of moisture. Make sure you're running the exhaust fan while you're in there, and let it run several minutes after you're finished.
2. Kitchens. Cooking also generates a lot of moisture that needs to be removed or it's gonna add to the problem. Use your range hood.
3. Garden Windows. House plants give off a lot of moisture.
Three possibilities:
1) The humidity is higher in the new part of the house. This can happen in new construction since the drywall and lumber is relatively moist when installed and takes 6-12 months to fully dry out. Plus of course there could be differences in how humidity enters the house, with a shower near the new construction.
2) It's cooler in the new part of the house, or at least on the new windows, due to poorer airflow through ductwork, etc, or simply something like having curtains on the windows in the new part but not the old part.
3) The area around the new windows was not properly insulated and air-sealed, and outside air and/or cold is infiltrating into the rough opening area.
From your description I'd guess #3 first, but would have to see things or ask a lot more questions to be sure.
There are 100's of reasons for humidity/condensation. The trick is finding it.
Humidity.
Remodeling Contractor just on the other side of the Glass City
First thing is check the humidity level. HD have a small gauge in the garden department that reads temp and humidity. Its with the weather stuff. This will give you a starting point.
Not to be too sarcastic ,butttttt what is hard to figure out?
Ancient leaky old logs with no vapour barrier and modern 2x6 with an extra layer.
You have a ventilation and moisture problem in one and a moisture and ventilation problem in the other.
The high quality windows throughout illustrate the deficiencies of each type of construction.
Ventilate the new ( with HRV or ERV )and seal the old (With Perma chink or whatever).
Edited 12/21/2008 12:04 am ET by s crough
heard that problem discussed on the radio and the recommendation was to open the windows 1/16" and it would go away
You have a serious moisture problem. You're getting more condensation upstaires becuse warmer (and moist) air rises.
The old log part of the house may have the same relative humidity level, but the logs have a high moisture-storage capacity and will buffer the RH. You don't have this buffer in the addition.
Also, the log part is undoubtedly leakier than the new. Leaking air (heating cold air and hence lowering the RH) is what dries out a house in winter. Fewer leaks in the new addition = higher humidity.
Get a hygrometer to determine the RH level. It should not be more than 40% in winter.
You need to first reduce the sources. Make sure kitchen exhaust hood and bathroom exhaust fans are used every time moisture is produced.
If that doesn't work, consider a dehumidifier or a heat-recovery ventilator (small ones are available).
Solar & Super-Insulated Healthy Homes
It should not be more than 40% in winter.
Robert,
"Winter" is different in Vermont compared to Dallas.
Many winter days and nights in Dallas the temp stays above 45 deg.
What is the outside temperature threshold where 40% Rh(or less) is the goal ?
I know each house is different..but in general below what temperature?
40% should be the upper limit is most homes during heating season, to prevent mildew. That limit is good down to roughly 20F, depending on construction. Below that temp the humidity must be reduced to avoid condensation on windowa and condensation within framing.
The mark of the immature man is that he wants to die nobly for a cause, while the mark of a mature man is that he wants to live humbly for one. --Wilhelm Stekel
got plants in the new part?http://www.tvwsolar.com
Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
we've got two fairly large potted plants in the master bathroom (north east end of new addition). We've also got our laundry room in middle front of this addition, with no door on it at the moment. I wonder if these two things are a part of the problem?
probably contributors, but I'd get a VB on the crawl space floor... if you have a dehumidifier, you might want to run that down there for a while, both before and after the plastic.http://www.tvwsolar.com
Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
thank you.
Crawl space open to earth is likely a large part of the problem.
Brand of windows?Jeff
"Crawl space open to earth is likely a large part of the problem."exactly!hey guys, my kitchen floor seems to be wet, no matter how ofteen I mop it up, I keep getting my feet wet when I walk in there""Oh, BTW, Perhaps I should mention that I have a leak from under the sink. Do you think that could be the problem?"LOL
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
No the tile is clearly defective ;-)
Do you have at least one quality carbon monoxide detector in the house?
There's always a chance that you're picking up some of this excess moisture from a partially obstructed flue/chimney or a crack/hole in the flue of a gas-fired or oil-fired appliance. The potential for CO poisoning is not something to take lightly.
I read up to "vapor barrier in crawlspace" and immediately had to post. I think that might be your problem right there. I'm not sure what your soil is like there, but here it is red clay, and it can hold onto moisture for a really long time. Double up your vapor barrier and tape the seams. Run it up the foundation a bit, and make an airtight joint there as well. Make sure you don't have standing water anywhere within at least six feet of the foundation, and if you do, find a way to remedy it. Run a fan in the crawlspace for a day, and then wait see if the problem goes away. If that doesn't work. Id say start looking for air infiltration. Best of luck!
Edit: Do you notice the condesation after the dryer runs a bit? I had to re-route my dryer vent run because the installers did a terrible job, I could feel warm air coming out of a switch from the wall behind it, alot of it! Also, buy a timer for the dehumidifier. Set it for when you notice the most condensation. I set mine for the dew point temperature outside, in the morning and late evening.
Edited 12/27/2008 10:04 am ET by arcflash
turn the humidifier down.
40% should be the upper limit is most homes during heating season, to prevent mildew.
The 40% standard is to prevent condensation. Mold growth requires, in addition to warmth, a surface moisture content for wood of 16%. Wood has an equilibrium moisture content of 16% at 80% RH.
Of course, continued condensation where drying by diffusion or evaporation cannot occur, can wet wood sufficiently to reach this EMC as long as it remains wet when it's able to warm beyond 50°.
Riversong HouseWright
Design * * Build * * Renovate * * ConsultSolar & Super-Insulated Healthy Homes
Other things besides wood mildew, and the problem is not the RH in the middle of the room, but the RH in the corner, or behind the dresser, as well as the RH around the windows.It's a rule of thumb, of course, but 40% is a reasonable upper limit -- an increase above that value will not noticeably improve comfort or reduce human "winter dryness" discomfort, and going above that limit greatly increases the risk of condensation (and associated mildew) in susceptable areas of the structure.
The mark of the immature man is that he wants to die nobly for a cause, while the mark of a mature man is that he wants to live humbly for one. --Wilhelm Stekel
"Winter" is different in Vermont compared to Dallas.
I didn't recall that the OP mentioned his location. He talked about cold outside.
Many winter days and nights in Dallas the temp stays above 45 deg. What is the outside temperature threshold where 40% Rh(or less) is the goal ?
It depends, of course, on the air and vapor tightness of the structure, and on the outdoor relative humidity. But, by my calculations, with an outside RH of 75%, any outdoor temperature below 40° could be problematic.
Riversong HouseWright
Design * * Build * * Renovate * * ConsultSolar & Super-Insulated Healthy Homes
Its not the windows. Get a hydrometer and see what your moisture level is in the house. Like someone else sed its moisture in the house has reached dew point temp on the windows.
Jeff,
It's not uncommon for windows to get damaged upon installation. Excessive hammering too close to the new windows early on in the project could've very well caused the seals to come loose. Once loose, the gas escapes, the moisture enters. I wouldn't rule it out completely. You'll know for sure once you've tried everything else and it's summer and the windows still have the moisture problem. Just because it's "high end" doesn't mean it was built to last forever...