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Community and Q&A

Good-Looking, Energy-Efficient Fiberglass Windows

drpepper | Posted in Energy Efficiency and Durability on

We are leaning towards a fiberglass window.. but having a hard time finding a fiberglass company that has a beautiful fiberglass window that is comparable to a Marvin or Unilux triple pane aluminum clad.

Is that true that fiberglass is the way to go? Trying to balance really efficient windows (max U .2 and min SHG .4 would be ideal).. and want beautiful looking windows. Thanks for your input.

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  1. Riversong | | #1

    Thermotech has a wood veneer interior option. But you might also check out Pella's new option of high SHGC Natural Sun glazing.

    Depending on your climate zone and solar availability, and whether you've incorporated passive solar design into your house, a less insulating window with higher SHGC can sometimes offer better net performance than a very insulating window with less solar gain.

  2. Primo | | #2

    Since you're looking for a comparable fiberglass window to Marvin, why not look at Marvin's fiberlgass window? Both their Integrity and Infinity ( & are aesthically pleasing, high performing, quality products.

  3. bcornwellco | | #3

    Alpen High Performance products. Fiberglass, beautiful.. Slim frame option. Triple and quad pane glazing. Leaps beyond Marvin/etc. Just look up reviews on here, they are all fantastic. Best of luck.

    Edit, post is old. The person above me bumped this thread for no reason.

  4. oberon476 | | #4

    From everything that I have heard and read, Enerlux makes a very nice window. It's unfortunate that someone there decided that spamming a building site is a good advertising move.

  5. ArchitectJudge | | #5

    I’m using Milgard ultra 650 fiberglass (black) being installed now and look great. It was $27K for double pane best price I found for the amount of windows I have: U value .25. (20 windows many quite large, 6’x4’ half casement).

    Good luck!

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