Shades w/ LoE i89
mmeerryy
| Posted in Energy Efficiency and Durability on
We bought windows with LoE i89 on the 4th surface of double panes windows (with a combo of LoE 180 and LoE 272 depending on the side of the house). I can’t seem to find info on if the combo of i89 with shades will cause worse chances of condensation than no shades. Does it matter if they are just roller shades vs the more insulating cellular shades? We’re in zone 4 of the Rocky Mtns and the house is pretty dry in our semi-arid climate.
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Thank you oberon476. I can do a test this winter. We have double paned clear glass now and haven’t seen condensation with the shades drawn but sounds like this may not be indicative of how the new windows will react with the LoE coatings. It also makes me wonder if the house is cooler, like with much lower heat temperature setting when not home (so air temp not as different than the cold glass), does that reduce the chances of condensation?
mmeerryy,
I inadvertently deleted my original reply when I only meant to edit it prior to seeing your follow up. Sorry for confusion.
If you currently have clear glass and you don't see condensation with the shades pulled, then I would not expect that you will have condensation problems when using a surface 4 coating with the shades pulled or not.
Although the surface 4 coating does lower glass temperature when compared with not having the coating, when used in conjunction with a surface 2 coating the temperature of the glass surface will still be higher than the temperature when using clear glass for both lites.
The only other consideration if you are planning on new windows is if your current windows aren't particularly air-tight and the new windows are. The tighter new windows can result in an increased level of humidity in your home compared with what you have now, and that could increase likelihood of window condensation as a consequence.
That’s a great thought, the tightness is something I hadn’t considered and would definitely be better with the new windows as ours are leaky now. I’m going to hold off on purchasing new shades until I see how the new windows perform in our house. Thanks again for your helpful insights.
Enough people comment about condensation on internally coated surfaces, that I am sure there must be something to it, but I have 4 sliders with i8? and they do not condense anywhere near what crappy insulated glass does.
That’s good to know and what we’re hoping for too.