Why do I feel cold on my right side when I sit near my new windows?
Bradybunchh
| Posted in Energy Efficiency and Durability on
I got triple-glazed windows installed, but I seem to feel cold on my right side of my leg sitting next to the new windows. Everything seems to be sealed.
Can someone give me a explanation, please?
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Replies
Scott,
There are three possibilities:
1. The outdoor air temperature is very cold. Can you tell us how cold it is outdoors when this happens?
2. There are air leaks near the window -- either air leaks between the window rough opening and the window frame (signs of sloppy installation) or air leaks between the window sash and the window frame (signs of a problem at the window factory).
3. The U-factor of the window is too high. If the U-factor is high, the interior surface of the glazing will be cool during the winter, and your skin will radiate heat toward the cold glazing. What are the window's U-factor specifications?
Just for completeness, it's also possible that the wall below or next to the window is not insulated or is poorly insulated.
It also depends on the window. With triple glazed windows, the frames are the weak spot and have higher U-values than the glass. There are windows available with specially designed frames for lower U-values, but just because a window has triple glazing does not mean it has a high performance frame.
Do these windows extend to the floor? For normal height windows, I would expect someone to complain about their arms or face feeling cold rather than their legs.
Do you have registers under your windows?
Hi thanks for response
I got a laser temp probe and found that the glass was between 20/21c ,but when I moved it to the sill it dropped to 12/13c and the facings were about 15/16c.
All the walls have been insulated
Windows are about half a metre of the floor
I don't know the u rating
Scott,
The interior surface of your glazing is at 68°F. That's quite good.
If your sill (stool) is at 54°F or 55°F, that's not bad, either -- but it may indicate an air leak near your stool.
Here in Vermont, when air leaking through window cracks can sometimes be at 0°F or -20°F (-18°C or -29°C), your problem doesn't sound serious.
While 12-13°C isn't terrible, it highlights a comfort and performance issue that is addressed by Passive House design. Humans typically feel a difference in mean radiant temperature of about 5°C, so even if your trim measured 15°C, you might feel a bit uncomfortable. The energy savings to rectify the situation at this point probably don't make financial sense, but if the comfort issue bothers you, you may be able to remove the trim and add insulation and/or thermal breaks to improve the performance.