It is condensation from the broad temperature differential and higher than tolerable indoor humidity. Even if the aluminum windows have a thermal break (foam insert) they are going to be your most conductive frame material and therefore get cold when it is cold outside. Cold surface + warm air = condensation. Most windows that are considered thermally broken are actually just insulated and not truly thermally broken. You can lower you indoor humidity and see if that doesn't fix the issue temporarily. I think we can agree that these are pretty irregular temps for Dallas.

WINDOWS AND PATIO DOORS CONDENSATION The information contained herein is provided solely for informational and/or educational purposes. JELD-WEN disclaims any and all liability associated with the use and/or provision of this information. Any reliance upon the information or advice is at the risk of the party so relying. The information contained herein may be changed from time to time without noti cation. © 2005 JELD-WEN, inc. and JELD-WEN, are registered trademarks of JELD-WEN, inc., Oregon USA. ® T he rst cold day of autumn hits. The windows fog up and water drips down the glass. A common reaction is to pick up the phone and dial the window manufacturer. But dont worry! This is not an indication that your windows are failing. The moisture on the glass is called condensation; a natural phenomenon that, in most cases, can be easily eliminated. Condensation occurs when excess humidity in the air releases on cool surfaces. The glass in windows and patio doors usually provides a visible, cooler surface that shows the rst signs of condensation. Windows in New, Energy-Ef cient Homes Homes built today are more energy ef cient and substantially more air-tight than homes built just a few years ago. As a result, air inside the home is better captured (saving energy), and there is less exchange with outside air (increasing interior humidity). Interior humidity builds up because the moisture from indoor activities has less opportunity to escape to the outside. You may never have had interior condensation in your older home but are now experiencing it. Family life style has a large impact on humidity levels. Activities such as cooking, long showers or baths, saunas, spas, and laundry contribute to humidity levels. Variations in these and other moisture-generating activities often result in one neighbor experiencing condensation and another not. Replacement Windows in Older Homes Condensation can also be seen in older homes where new windows have been installed to increase energy ef ciency. The new, replacement windows are installed in an air-tight manner according to building codes. While this practice keeps heat and air-conditioning from escaping, it also prevents moisture in the air from drying out. The older windows had the opposite effect. They allowed heat and air conditioning to escape, but air exchange with the outside air helped dry out moisture in the air. INTERIOR CONDENSATION High interior humidity can lead to structural damage to your home (e.g. wood decay) and health hazards (e.g. mold growth). Because these effects frequently occur unseen in the wall cavity, the visible sign of condensation on glass is a good clue that humidity levels are too high. Condensation on the interior surface of glass is almost always due to high levels of interior humidity. Therefore, it is important to control interior humidity. Use a hygrometer (an instrument that measures relative humidity in the air) to monitor indoor humidity levels. This chart indicates the humidity level at which interior condensation may occur for different outside temperatures. As shown in the chart, when the outside temperature gets colder, a lower interior humidity level is needed to prevent condensation. Outside Air Temperature Inside Humidity at Which Condensation Occurs 20° Over 35% 0° Over 25% -20° Over 15% The values in this chart are based on winter conditions of 70° indoor temperature with 15 mph outdoor winds and double-glazed windows. CONDENSATION OCCURRENCES Condensation Page 2 JGI012 09/05 AVOID INTERIOR CONDENSATION Consider installing dual-paned, insulating glass (IG). IG units tolerate more indoor humidity before "fogging up" than single-pane glass units. For further protection, consider Low-E (a coating on glass that reduces radiant heat-loss and the passage of ultraviolet rays). ■ Raise the average temperature of the house one or two degrees. Depending on many conditions, this can greatly reduce condensation. ■ Open window blinds for air circulation. Closed blinds trap warm air in the space between the glass pane and blinds. This air cools and releases moisture in the form of condensation. Blinds should be hung at least 4" away from the window glass. ■ Use a ceiling fan to circulate warm room air toward windows. ■ Relocate heat vents to beneath windows and patio doors. ■ Do not block heat vents with furniture or other objects. The placement of these vents is intended to promote proper air circulation throughout the house. This air circulation helps moisture in the air to dry out and also distributes heat more ef ciently. ■ For unoccupied and unheated rooms, keep interior doors open. This promotes proper air circulation throughout the house. ■ Vent all appliances to the outdoors. For example, if a dryer is vented into the attic or basement, all the moisture from drying wet clothes is released into the house. ■ Run exhaust fans in kitchen and bathrooms. ■ Vent the attic and crawl spaces so moisture has a chance to dry out. Vent ducts should be clear of obstructions. ■ Make sure all vent ducts are clear of lint and other obstructions. ■ Turn humidi ers down as the temperature outside gets colder (if used for medical purposes, consult a doctor). ■ Be sure humidistat is located within the living space and not at the furnace outside of the heated part of the house. ■ Use a dehumidi er. ■ Dont dry rewood inside. ■ Have an air exchange system added to your heating system. SOME CAUSES OF TEMPORARY CONDENSATION ■ Building materials in new construction contribute many gallons of moisture to the interior air and it often takes one year for all of the moisture to escape. ■ During the rst few weeks of heating during the cold season, condensation can be a problem due to the release of moisture absorbed inside the house throughout the humid summer. ■ Quick temperature changes during the heating or cooling season can contribute to higher levels of condensation. EXTERIOR CONDENSATION When the temperature of the exterior surface of the glass is cooled below the dew point of the outside air, moisture forms on the exterior side of the glass. Then, as the glass temperature rises above the dew point, the moisture evaporates back into the air. Three main conditions promote exterior condensation: ■ High humidity in the exterior air ■ Very limited or no wind ■ Clear night sky AVOID EXTERIOR CONDENSATION ■ Close window coverings to reduce cooling of the glass by air-conditioning. ■ Remove or trim outside shrubbery near glass to promote air circulation. WOOD WINDOWS & PATIO DOORS As condensation occurs over time, moisture may penetrate wood. This could lead to wood decay. To help prevent this from happening, keep windows and patio doors nished or painted and follow the suggestions in this document to reduce humidity. Condensation Page 3 JGI012 09/05 VINYL WINDOWS & PATIO DOORS Vinyl windows and patio doors have a "weep" system designed to drain water to the exterior. If this weep system is not draining properly, moisture may enter the surrounding wood structure and cause water damage. Clean dirt and debris from weep holes with a thin piece of wire. ALUMINUM WINDOWS & PATIO DOORS Aluminum is especially subject to condensation because of its high thermal conductivity (a measurement of the ability of a substance to transfer heat). The temperature of aluminum will quickly change to the air temperature around it. The colder the outside temperature, the colder the aluminum frame and the more likely condensation will occur. SUMMARY Condensation is a natural phenomenon that occurs on exterior and interior glass surfaces. In nearly all cases, it is not the result of a defective window or patio door. Care should be taken to reduce humidity with proper air circulation. If condensation persists after following the precautions suggested in this document, contact a quali ed heating and air- conditioning professional. Condensation between glass panes is a different problem. If moisture is still present after cleaning the interior and exterior sides of the glass, seal failure (when the seal between two panes of an insulating glass unit has broken) between the glass panes could be the cause. If so, please call us for assistance. CONTACT US For questions, feel free to contact us by phone or email. ■ Email: customerserviceagents@jeld-wen.com ■ Phone: 1-(800)-JELD-WEN / 1-(800)-535-3936

It is very likely that you have collapsed glass. Many window companies have/had this problem. Andersen has a repair procedure and the warranty on your windows ends this year. One way to tell is to open a sash. Place an index finger on either side of the glass, opposite one another. Move from the edge to the middle. If your fingers seem to get closer in the middle, the glass is collapsed. This is where the argon has leaked out, but the ambient air is unable to get in, creating a vacuum.....collapsing the glass. Call Andersen @ 1-888-888-7020. Give them the visible glass size of the sash and the date code in the corner. The service includes opening the seal and letting a bit of air in which makes the glass thickness uniform. If this is the issue, no more condensation....unless the humidity is too high in your home.

Is the film on the glass? It is likely just a residue of paint that was dissolved by the Xylene. What are the frames of your windows made of? Hope they didn't use that liberally on the frames if they are vinyl. Sounds like the glass just needs to be cleaned properly.