Low-E Glass and Fading

[Buck Turgidson]

I have a bay window with low-e glass that I had installed 10 years ago. I have noticed that my curtains have faded somewhat. The curtains are only about 6 years old, and only get sun in the wintertime when there are no leaves on the trees.

Should low-e glass do this, especially after only 6 years. The glass does have a tint, and a sticker on them said low-e, so I doubt they're clear glass.

Just wondering how much UV low-e is really supposed to block.

Thanks.

[Don Phillipson]

You did not say whether these curtains are lined or not. Linings delay fading from sunlight.

[Frank]

This definition might help:

low-e glass transmits visible light but is opaque to infrared or heat radiation. I suspect UV passes too which would explain fading. Frank

[George E. Cawthon]

Yes, to the question of whether the curtains would fade in 6 years. Low-e is about heat loss so that means blocking infrared. Window glass transmits a lot of UV and visible light which causes fading of materials. Films that block fading will also block a lot of light. Almost any current especially on a south side will fade rapidly, that's probably why curtain liners are usually/often white.

[Joseph Meehan]

Low-e usually blocks at least some of the UV that does the damage. However Low-E really means IR block not UV blocking. How much varies. The ones I have seem to be doing a good job, but they have not totally prevented any fading.