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condensation on interior windows

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Nov 24, 2013, 09:48 AM
condensation on interior windows
We have a home we totally remodeled over the last year. Installed Pella Low E wood clad windows and a Pella wood sliding door. This morning (temp is 14 degrees outside) there is condensation on all windows. Not my first rodeo with this type of work. We have block full basement with fireplace downstairs. Not sure where/how this is happening. Any suggestions?
Nov 24, 2013, 11:44 AM
Excess interior humidity will manifest on even the very best windows. Be sure to use all vent fans (vented/exhausted to outdoors not just attic) when showering/bathing/cooking and for a time after use, to expel excess moisture.

A propane or gas fireplace (in use) also can increase humidity indoors. If you have a humidifier, turn it down lower, or off for the time being.

Is this a sudden cold spell? Often heat systems operation can gradually dry the indoor air in a few weeks.
Nov 24, 2013, 12:20 PM
Thanks Conrad we do have a dehumidifier and will let it run more....maybe that will clear up the problem. we have the damper shut on fireplace and have a 5/8 piece of plywood in front. there is a small like cold storage closet in basement at bottom of stairs that we believe has outside moisture getting in. We are still in remodel phase of basement as it is total gut job also....any other suggestions appreciated thanks
Nov 24, 2013, 02:05 PM
Conrad is the man. Big Grin This condensation actually shows you that your window and door upgrade is doing what you had intended for it to do. Save energy.
Boy all those days and lessons learned at the millwork never leave a person.

Popeye only reached for the Spinach can as a last resort...
Nov 25, 2013, 09:45 AM
Thanks we had built a new cabin/house in northern Michigan where the average snowfall is like 72 to 96" and never had this problem. We also had two skylights never had a problem we were wondering what was going on with this house...hopefully it will be a quick fix...Thank you for the input.
Nov 28, 2013, 09:42 AM
Your problem could be fixed with a dehumidifier, but not a 100% cure as all homes are different. Running kitchen range, microwave and bath fans factor in as well.

Popeye only reached for the Spinach can as a last resort...
Nov 29, 2013, 10:54 AM
your house is now energy-tightened, and the humidity stays trapped. we used to have ice on our window bottoms before we replaced all the blown Thermopane and caulked all the floor and envelope-piercings. now we have a little water for the cats to lick. at 40% humidity, we shock the cats, but the windows are pretty clear. normal humidity is about 50% for us, and we get a little condensate. big meal days like Thanksgiving and Christmas, humidity goes up around 60% and there's more.

that's why you also need to pay attention to the finishes around the windows, too. paint as needed or renew the varnish so the water that does develop from condensation doesn't get into the wood.

sig: if this is a new economy, how come they still want my old-fashioned money?