Ice and moisture on the windows

[holg]

Here's the home. Main floor and a basement; northern Wisconsin, 2000 sq ft.; windows double pane, 2x6 walls, well insulated and caulked; attic with 22" insulation, no ice dams; 1/3 of basement is dirt floor crawl space with dirt covered with plastic; 3 exterior doors; had house professionally tested after remodeling myself over the years and would qualify as Energy Star home. Guy said house was "too tight" and needed more fresh air--installed a direct air inlet that I can easily monitor and it does let in cold air down there in the basement; basement to main floor not closed by any doors, straight shot up, no obstructions.
Here's the windows: 1/2 of them 18 years old, double pane, no Argon or Low E; 1/2 of them 3 years old, some of which are Low E, some not, none with Argon (Semco windows--made in WI).
Here's the heating: Wood stove centrally located on main floor, nicely heats living/dining/kitchen and hallway to
bedrooms; 3 bedrooms, 2 baths heated by a hydronic run when it is on, but the wood stove keeps that part of the house compfy generally without being on; basement has it's own hydronic run to keep that 60s (mostly storage and utlities down there).
Woodstove: Hearthstone Heritage, doing a fine job.
Current humidity level in the home: 38low 40s (after this weekend lots of hours running the clothes dryer on no-heat cycle, and off and on running one bathroom vent fan).
Here's the problem: With the wood stove humming along, no need for upstairs hydronic to be on. If I put it on, would roast us out of the house (right now it is 70--72 in the livingroom and I am wearing shorts--it was -17 last night and 0 outside now). Without the hydronic, no heat under the windows; even if hydronic on, no forced air to move the heat.
What I've done: just bought eight 4" fans, three 8" fans and used the three 10" fans I had previously and aimed them all at the windows--that does a very good but not complete job of clearing the bottom of the windows, some still have some moisture along the bottom, some still have some ice in the lower corners.
I am thinking of building "inner storms" with the heat shrink plastic. I am thinking of next year starting to slowly replace the casements glass with Low E and Argon and not the whole window unit (some of the lower wood parts of the crank-out parts of the casements are looking rough from years of this problem).
Windows stay good until about 5 degrees; lower than that, and the problem starts. Without the fans, major moisture and ice, depending on which room (area with wood stove less effected by the cold).
Any insight would be appreciated--thanks for reading.

 

[begreen]

Inner storms with heat shrink should do the trick.

 

[DBoon]

I agree, inner storm plastic would work. Do you have storms on the outside? Also, if the plastic over ground in the crawl space is not tightly moisture sealed, it's likely not doing the job you think it is and the ground is likely putting moisture into the house.

 

[begreen]

I did this on our large windows before they were replaced. Use very good tape. I found 3M's to be the best. The cheaper stuff dried out and was a bear to remove.

 

[elmoleaf]

Get a dehumidifier.
If outdoor temps are in the 10-20s, then your indoor humidity should be no more than about 35%, otherwise you'll get condensation on the windows. At lower outside temps, you'd need to keep the humidity even lower.
Obviously, older windows with lower R value allow colder glass surface temp and make it easier for condensation to occur, so the window film will help on your older windows even if you do nothing else.

 

[WES999]

I had the same problem.
This is what I did:

No more problem.

 

[maple1]

I don't think those humidity levels are high enough that I would add a dehumidifier.

Are those levels measured at the same place that the icing is?

Icey windows might be taken as a sign of high humidity by some - but they can also be seen as a sign of a tight house, which would lead to pools of little air movement or little air washing across very cold window surfaces. Baseboard heat can create upward air currents that would wash across windows and reduce it, so if the baseboards aren't heating there's even less air movement. I have the odd window that ices, but don't worry about it. It's usually in an intermittently high humidity place - bathroom. I don't think I could get the humidity level low enough in my house to prevent it all together. Right now my meter says 34%.

I would do the interior window insulating film thing, should be cheap & easy quick temporary solution. Then better windows might also help.

I am curious though about the direct air inlet that was installed in the basement - or what exactly that was. If there was no corresponding outlet to let or exhaust stale air out, I'm not sure that would do too much. Unless I'm misunderstanding something. Plus whatever is coming in will be very cold - not helping the heating situation any. An HRV would be a good solution, but those get tricky to do in a retrofit situation.

 

[holg]

Are those levels measured at the same place that the icing is?

I am curious though about the direct air inlet that was installed in the basement - or what exactly that was. If there was no corresponding outlet to let or exhaust stale air out, I'm not sure that would do too much. Unless I'm misunderstanding something. Plus whatever is coming in will be very cold - not helping the heating situation any. An HRV would be a good solution, but those get tricky to do in a retrofit situation.

Thanks all for the replies, and I will probably try the inner storms with the plastic film--one question is do you keep those from year to year without the film getting wrecked-- I am trying to imagine storing them for a couple of dozen windows and I would think they would need to be redone often. Also getting a tight fit with the foam edge looks like it might be tough, but doable. Any suggestions on that?
As for the humidity levels, I have 3 humidity gauges throughout the home, and they all read about the same; they are not located on window sills however.
As for the direct air inlet, it is simply a screened hole about 6-7 square inches surface area, in a portion of the basement where there is a 6' x 12' overhang outside so no rain or snow ever bothers it. I hang a piece of light ribbon by it on the inside of the house and it waves in the outside-to-inside breeze. With no demand for extra air, it still lets some in, with the wood stove in coaling stage maybe a little more, with the stove humming away good or with exhaust fans running it's a healthy small gale, but I think that is my primary air inlet to the home and don't worry about the cold it adds.
And I am beginning to think that the observation that the crawl space with the heavy plastic may be allowing more moisture into the home than I thought might be correct--the plastic isn't sealed to anything--just laid over the dirt.
And for an experiment, I am running my dehumidifier I use in the summer right now, but I don't think mine does a very good job when the humidity is 35--40%; seems to run with little accumulation of water.

 

[maple1]

Dehumidifiers don't work well in cooler temps either. I have a humidty meter thing on a shelf here. It has different coloured zones for 'too dry', 'too wet', etc.. Right now my humidity is saying 34% (via this guage & another separate one), which is right at the dividing line between 'too dry' and 'comfortable'. IMO, 34% is pretty good.

 

[DougA]

I used to get a lot of water and icing up on my windows and didn't see that as much of a huge problem. The important thing is that the humidity level is good for people and pets. The last few years, I am heating solely with wood and the humidity is too low. We've always got a pot of water on the stove plus a humidifier on. My nose is always took dry and the dogs have rashes. Way too dry and zero moisture on the windows!

When I had the moisture and ice, my wife or I would walk around the house mid morning and wipe the moisture off and put the towels outside to dry. Make sure that you don't have any mold growing on the window sills. In the Spring, wipe them down with a bit of bleach mix on a rag to kill all the mold.

As long as you are getting condensation only on the glass and not inside the walls,, you are OK.