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Zola Windows

William Dempsey | Posted in Energy Efficiency and Durability on

We are beginning a new home. I am late in ordering windows and I have a couple of questions. I am considering both Alpen and Zola windows. The windows we are considering from Zola are the uPVC, triple pane. From Alpen they would be true triple pane (no film) fiberglass frames. The two come in within a small percentage difference in price. Can anyone respond as to their experience with either or both companies regarding customer service, product reliability and so forth. With Zola tilt and turn I am concerned that the windows will need constant adjustments and I will have pay for continued service calls. I understand having a rep visit after they are installed and paying for an initial adjustment. I am not interested in having continued adjustments in the future. This will be expensive. Second, they mention between 7-9 weeks delivery from initial order date. I am concerned because once the order is place I will be stuck if the delivery date is not met. They do not guarantee a delivery date.
I am considering Alpen for a couple of reasons. The first being, quicker delivery date. The second being made here in the U.S. they should be able to predict a delivery date with more confidence. I really like the tilt and turn features of Zola. Any comments or suggestions will be appreciated.

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  1. Sam McAfee | | #1

    Both products are very good. The most important thing to compare is:
    -lead time Zola is 12+ weeks and Alpen is ??.
    -secondly, assuming air tightness and spacer values are about the same, what is the center of glass for the Alpen unit? Zola has a Ug(si)=.5 (Ug(ip)=.089). On the Alpen site there is a wide range of potential glass performance numbers. So just make sure you are comparing apples to apples on these fronts.

  2. Mike M | | #2

    Jack, another consideration is the frame material and expansion and contraction. To my knowledge, fiberglass will have a lower expansion and contraction rate than the unplastisized polyvinyl chloride. This could have an effect on longterm durability of seals.

  3. William Dempsey | | #3

    Thanks for your help in this. This is a big decision, I think I all have to compare "apples to apples" and jump in and order. Sounds as though both are quality products.

  4. William Dempsey | | #4

    Thanks for the information. That is a valid consideration. I understand that the uPVC product is better that standard PVC. However, I believe you are correct in that Fiberglass will expand and contract less.

  5. GBA Editor
    Martin Holladay | | #5

    You wrote, "I understand that the uPVC product is better that standard PVC."

    You're wrong. All vinyl window frames are made of unplasticized PVC. It's all the same stuff. Marketers who pretend that "uPVC" windows are different from other vinyl windows are making a distinction that doesn't exist. It's hogwash.

    Plasticized PVC is the flexible stuff used for flooring and cable insulation. Unplasticized PVC is the stuff used to make window frames.

  6. William Dempsey | | #6

    Thank you for the clarification. Maybe I have misunderstood, but it seems to me that certain manufacturers of imported windows are leading consumers to believe that a uPVC window product from Europe is superior to a PVC window from the U.S. That being said if the energy efficiency ratings are near the same would you choose fiberglass or uPVc.

  7. GBA Editor
    Martin Holladay | | #7

    Fiberglass window frames are superior to vinyl window frames. That's why they cost more.

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