Shop Products
Houzz Logo Print
creek_side_gw

Opinions Needed Regarding Some Window Brands

creek_side
14 years ago

We are building a passive solar home. The design calls for casement windows with a high solar heat gain coefficient (SHGC) and a high (for windows) R-factor. Most available windows have a low SHGC and are unsuitable for passive solar use. Even before we selected a contractor, we started looking at windows, knowing window selection would be critical.

After looking around, we were told by one window supplier that the Marvin Integrity line just met the specs. We looked hard at them and liked what we saw. We have been planning to use them from the get-go.

Today, our builder's regular supplier, who also handles Marvin, determined that the Integrity line really does not meet our specs. The confusion seems to have originated with some Marvin documentation that could have been better written. In any event, we are back to square one.

Our builder's preferred window supplier also handles Windsor, Semco, and Jeld-Wen. According to the owner, these brands can supply their windows with special Cardinal glass designed for passive solar heating. We now have to consider Windsor, Jeld-Wen, and Semco.

What are your thoughts on these brands? All opinions welcome and appreciated.

Thanks.

Comments (12)

  • mythreesonsnc
    14 years ago
    last modified: 9 years ago

    Hi Creekside,

    I'm not a window expert by any stretch of the imagination, but I did go to a store last week to look at Windsor windows. In the sales showroom they also sold Marvin and Semco. I have to say the Windsor was a bit disappointing compared to Marvin. I asked a few questions about Windsor vs. Semco --- if I remember correctly, they are very similar, but windsor has better doors, and many more options standard. Semco gets tricky when you get to doors. Just don't want you to look only at windows, make a decision and then find the doors are a problem. They might not be in your situation. One thing the windsor guy told me in the sales pitch is that the windows are made from extruded aluminum vs. rolled aluminum (like a coke can). It sounded good to me, but DH was a bit less impressed with that distinction. I looked at Pella architect series last weekend and felt they were a bit more heavy duty looking than the Windsor. If I remember from an earlier post, aren't you in NC? If so, Windsor is manufactured in NC (as well as in Iowa, I believe). Finally, I spoke with one of my builders about Windsor --- they would save money vs. Pella architect. He feels the quality of Windsor is a very good value (and they have a good warranty as well). He said in his spec homes he puts Pella because people recognize the name. But, in a higher end custom build where people are concerned about a good quality window, but not necessarily the sticker in the window, he often uses Windsor.

    My suggestion, find your local windsor dealer and they will likely have some of the other brands as well. You will be able to compare them side by side. I thought they were nice, but not great. We do still have them on the list though.

    I'd love to hear your final analysis as we're still trying to make a decision. Good luck.

    Rachel

  • creek_side
    Original Author
    14 years ago
    last modified: 9 years ago

    We are building in the Knoxville, TN area.

    We looked at Jeld-Wen, Windsor, and Semco today with our builder. The Jeld-Wen was junky compared to the other two, so we have eliminated it. The Semco factory engineer happened to stop by, so I got the full factory spiel, which was interesting.

    The Windsor has a deeper reveal than the Semco, which gives it a better looking exterior, but Semco seemed better technically. They make their own glass modules using an insulating spacer around the edge. They also have a better casement latching system and foam the top and bottom extrusions and all four corners.

    We decided on Semco over Windsor, but only if we can't find a fiberglass window suitable for passive solar use. We are now in the process of investigating Serious Windows from Serious Materials. They have a rep in Chattanooga, which may be close enough. We have to talk to our builder about that.

  • crazyone
    14 years ago
    last modified: 9 years ago

    can i ask more about the passive solar.. we asked our architecht to go with this as we heard it was good for our CND location for good sun use in summer and winter and he also said the over hang was important.

    You say casement windows are needed for this, any other specifics?

  • creek_side
    Original Author
    14 years ago
    last modified: 9 years ago

    Take a look at the web site I have linked. You will find a lot of information there.

    There are probably three things that can be difficult with a passive solar home. First, obtaining a suitable buildable home site. Second, finding a builder that will do things the specified way instead of "his" way. Three, sourcing windows with the right characteristics.

    If you live in Canada, you probably won't have to worry about number three so much. There seems to be more manufacturers of suitable windows in Canada than the US.

    Here is a link that might be useful: Sun Plans

  • brad_begin
    14 years ago
    last modified: 9 years ago

    In selecting fiberglass windows with passive solar glass options, it is important to select windows that provide for both a high solar heat gain (high SHGC) and also excellent insulating ability (U-value)--let the energy in and keep it in. Wes Gilmore with Serious Materials at 303-530-1150 is knowlegeable and helpful in describing the fiberglass product offerings of Serious Materials designed for passive solar designs. Another excellent source of information is the Efficient Windows Collaberative website at www.efficientwindows.org.

  • creek_side
    Original Author
    14 years ago
    last modified: 9 years ago

    In selecting fiberglass windows with passive solar glass options, it is important to select windows that provide for both a high solar heat gain (high SHGC) and also excellent insulating ability (U-value)--let the energy in and keep it in. -- brad_begin

    Brad, I see you are the Director Of Operations for Serious Materials. The real difficulty is finding windows with a high SHGC and a low U locally. They are not readily available in all areas, especially in the South. Builders are rightfully loathe to order windows from remote suppliers due to potential warranty/service issues, which are best handled by a local rep.

    It doesn't help when window manufacturers refuse to list their dealers and reps on their web sites. I would expect that a business headquartered in the heart of Silicon Valley would "get" the Internet, but apparently not.

    I detest having to fill out a contact form just to find out who might be carrying the product I am interested in. It is not helpful when someone sitting in an office in Sunnyvale thinks they know who is convenient to me and who isn't. They don't.

    I want a list of all your suppliers in the state and the neighboring state. Then I will check them out locally, and I will decide which one I will deal with.

    A web site with less glitz and more information would be a good start.

  • oberon476
    14 years ago
    last modified: 9 years ago

    Creek Side,

    The working part of your solar gain (or no solar gain) windows is the LowE coating.

    There are two primary types of coatings available - hard coat and soft coat; and there are three categories within the two types - high solar heat gain, moderate solar heat gain, and low solar heat gain.

    Hard coats are primarily florine enhanced tin oxide that is applied while the glass is still hot in the float furnace using a process called Chemical Vapor Deposition or CVD.

    Hard coats, also know as pyrolytic LowE, were the first coatings available and are generally thought of as High Solar Heat Gain (HSHG) although there are low solar gain versions available - often using tinted glass as part of the application.

    Soft coats are applied to the glass in vacuum chambers using a process known as Magnetron Sputter Vacuum Deposition or MSVD, which really doesn't mean much to anyone outside of the coating world, but it is kinda fun to say.

    Soft or sputter coats are applied as multiple layers of metals and metallic oxides. A typical soft coat might consist of 7 to 11 layers of different metals, but not all of the different layers actually affect the penetration of heat thru the coating.

    Most soft coats use silver as the operative ingredient, but other metals can be used such as titanium or even stainless steel. The layers in a soft coat are very thin - the layers are measured in angstroms or "how many atoms thick". A single layer in a soft coat might be no more than 50 atoms in thickness.

    Soft coats are generally considered to be Low Solar Heat Gain (LSHG) by most folks because they do perform very well in that capacity when compared to hard coats, but there are moderate and high solar heat gain soft coats available as well depending on the number of layers of silver (I am going to use "silver" when talking about soft coats simply because the vast majority of soft coats used are silver-based). A single silver coating would be a HSHG, a dual-silver coating would be a MSHG, and a triple silver coating would be a LSHG.

    All LowE coatings work by blocking radiant energy, primarily in the Infrared or IR spectrum, but the differences between coatings pertaining to high versus low solar gain results from what portion of the IR spectrum is blocked.

    First, all light carries heat. If you have a window, you are going to get heat passing thru it no matter what you do because even visible light contributes to a good bit of radiant energy gain or loss thru a window.

    What a LowE coating primarily does is limit the amount of heat as IR (and to a lesser extent visible) energy that passes thru the glass.

    Why it works is based on the fact that the infrared energy spectrum is divided into near, mid and far, and when dealing with LowE performance we are talking primarily about the near infrared and the far infrared.

    In simplest terms, near infrared is direct solar gain while far infrared is heat that isn't direct solar gain.

    When the sun shines on you and you are feeling its heat directly, you are experiencing near infrared IR. When you feel heat radiating off a stone wall that was warmed by the sun, you are experiencing far infrared.

    All LowE coatings work by blocking far infrared. The heat that a home's heating system puts out in winter is far infrared. All LowE coatings will block a significant portion of that spectrum resulting in keeping far infrared heat inside in winter and outside in summer.

    But, while coatings block far infrared, they don't all affect near infrared the same way. A HSHG coating allows near infrared (direct solar energy) to pass thru the coating while a LSHG coating blocks energy in the near infrared spectrum. Obviously a moderate gain coating is somewhere in the middle.

    Many folks, especially in Canada, generally consider that hard coats are superior to soft coats for high solar heat gain applications because they simply passed more solar energy than do any of the soft coats. However, there are softcoat high solar heat gain coatings that are as good or better than the best hard coats in high solar heat gain applications.

    Typically the lower the SHGC the better the U-value of an IG with coated glass. LSHG coatings outperform HSHG coatings in U-value performance.

    But in a well designed solar-home the advantage of solar heat gain could offset the slight loss of insulating value in the windows.

    In a high solar gain application, you want to ensure that the coating is on IG surface 3 - typically, most coatings are applied to IG surface 2, so be sure to specify a high solar gain coating on surface 3 - no matter what the window you buy.

    I would also suggest (and this may be already in your plans), that you avoid placing high solar gain units on any side of your home other than direct south. Adding high heat gain windows on the east or (especially) west side is very likely to offset any advantage that you gain by having south-facing high heat gain windows.

  • creek_side
    Original Author
    14 years ago
    last modified: 9 years ago

    Our plans specify high SHGC windows for the south side only. Again, the great difficulty in this area is finding windows that meet the specifications. Other than the very expensive custom brands, in which it is possible to specify virtually any type of glass, there is almost nothing available.

  • energy_rater_la
    14 years ago
    last modified: 9 years ago

    Hey O.
    Glad to see you back.

  • oberon476
    14 years ago
    last modified: 9 years ago

    Hi ERLA.

    Good to see you as well. I've been around now and then, what have you been up to? Busy in your part of the world?

    creek side,

    The companies that you mentioned, other than Serious Materials, and including Integrity, use Cardinal LowE coatngs. Cardinal's 179 coating offers high SHGC and decent U-factor'

    You might try by passing the distributor and calling any of the companies that you are interested in and asking if they will use the 179 coating and if they will glaze the coating to surface 3.

  • creek_side
    Original Author
    14 years ago
    last modified: 9 years ago

    Cardinal 179, which is our architect's preferred glazing material, is not available from most companies, except with full custom windows, which are out of the budget. Marvin Integrity will not supply windows with 179, period. They are adamant about it. A local windows supplier has already been through all that with the factory.

    Other than Semco for certain, and possibly Windsor and Jeld-Wen, none of the window brands available locally will install 179, except for the aforementioned custom window manufacturers.

    I have already been down this road, which is why I requested experience with the three specific brands that I asked about in the first post in this thread.

    Serious Windows may be available from a non-local source that isn't too far away. We have an appointment with them tomorrow for a look-see. They appear to be very new to the window supplier business. I'm not sure what to expect.

  • willinak
    13 years ago
    last modified: 9 years ago

    Creek_side, can you give me (us), a followup on what you went with and the results so far?
    Very curious about Cardinal 179.