• NFRC has announced they are exploring the possibility of rating windows and curtain walls for daylighting.  The article goes on to explain that there are a lot of variables, a lot of factors going into this.  Some points for them to consider:

    1. They mentioned building orientation as a key factor.  Yes, but that’s only one part of the equation.  The other is latitude – how far north/south of the equator the building is located.  Another factor they mentioned was solar angle, which not only changes hour by hour, but minute by minute, if not second by second.  The incident angle of the sun on the glass changes how much actual light moves through the glazing.  How will that be modeled and standardized?
    2. What about surrounding buildings?  Daylighting out in the middle of the prairie might be a little different than downtown NYC and surrounding conditions, topography, etc.
    3. And what floor are we talking about?  The 5th floor in NYC’s going to see a different amount of sun than on the 35th floor on a high-rise building or on the 1st floor on a building that’s sitting out in the middle of an open field.
    4. What about the window framing and the shadows it casts as sunlight comes through the windows?  As the sun moves across the sky, isn’t that going to change, too?  How will that affect the daylight rating?
    5. What about weather?  Clear and sunny isn’t the same as cloudy and rain (come to Seattle, I know).  What about snow?  Or better yet, the day after a snowstorm, or reflectivity off ground conditions?

    Given more time, more points could be added, but hopefully you get the drift.

    But what I don’t get is don’t architects already do this, especially through LEED, which provides daylighting credits?  Why is there a need for a separate daylighting rating system? Are there daylighting aspects in LEED that fall between the cracks?

    The glass manufacturers have for as long as I can remember listed visible light transmittance in their Sweet’s catalogs and online technical data pages, along with solar heat gain coefficients, shading coefficients, etc.  That works for the present system; it’s what’s used to develop the LEED points.

    All we can ask of the NFRC at this point is to consider what, if anything, this will add to the building owners who eventually will have to pay for any testing or certifications that may come out of this.  And that any rating system reflect what the industry as a whole believes will make life better for all concerned, from the subcontractor up the line to the building owner.

    That may have been the case with the residential window rating system.  It’s not been the case with the commercial/site built certification process, which is still not where it should be to benefit the industry (my opinion).

    Your thoughts?  I’d love to hear what others think about this issue.

  • Dear Santa:

    Man, has it been a tough year in the glass biz!  Haven’t been many highlights this year.  Businesses closing, filing bankruptcy, or up and disappearing without a known cause.  People changing seats, or otherwise aren’t where they were a year ago.  I don’t know what you pay your elves, but how are they holding up?  Did you have to cut benefits or salary to stay even?  I gotta believe there are a lot of parents looking to you to pick up the slack for the layoffs, jobs that never got off the boards, etc.

    Someone did a cartoon about Christmas a couple of years ago:  “What I really want for Christmas this year is a project in touch with reality.”  On costs, on schedule, on what it really takes to do it exactly right to meet the owner’s, architect’s and everyone’s expectations with a fair profit.  Not fat, not barely getting in the black, but fair and reasonable. One where it hasn’t been cut out from under us before we start, that just because it was ordered today doesn’t mean it can ship tomorrow.

    Do you know construction unemployment’s the highest it’s been in a while?  Did you change how you operated?  Everyone’s looking internally to see if changes should be made.  We’re doing that here, too, trying to find better/cheaper/faster ways of doing what we do best.

    Can you bring everybody a dose of faith, hope and charity that we won’t all throttle each other as we implement these changes?  Faith in the direction we’re headed, in the management team for pointing us in the right direction (heck, they’re part of the change, too with just as much to risk as any of the rest of us further down the totem pole).  Hope that it will all be for the good, and charity for those with less opportunities than we have to steer our own ship, that we can still find a way within ourselves to support those worse off than we are.

    It’s been tough. One guy (you know him, I think, he’s a big real estate tycoon, owns a couple of casinos) we all know and love in the glass industry says he wants to be our president.  Of the USA, not GANA.  That would be ok, but please bless him that he not dis his own countrymen by going overseas to buy windows or curtain walls for one of his projects.  He likes the products his countrymen make, he says, but the exchange rate makes it too easy for him to go elsewhere.  Please bless him with a change of heart.

    Truth in advertising would be great.  You got anything that can help there?  Especially when it comes to this green building stuff.  We hear all the time that glass can be recycled.  But every time there’s an old building demolished, they leave the glass in it.  And blow it up and the glass ends up in the landfill.  Why don’t they take LEED credits away for that from the building that’s built on the demo’d site?  What I’d like for Christmas is an easy way to strip IGU’s of their spacers and seals, easily remove the low-E or reflective coatings.  To delaminate laminated glass.  For these processes to be economical.  I’ll ask my boss for start-up equity and get that business going.

    Any way you can infuse the economy?  The Dems and Repubs are having their customary who’s in charge, who’s going to get which federal handouts.  Heck, the folks in DC said they didn’t want to extend unemployment benefits, there wasn’t enough money to pay for it, but wanted to keep the old tax cuts in place.  Huh?  This new health insurance thing has everyone scared as to what’s coming.  Anything you can do settle that down?  And any way to speed up the recovery faster’n the 2014 predicted at BEC (and other venues) this year?

    I know this sounds like I’m complaining.  I’m not.  Just so you know:  I’m grateful for a good job, to be able to provide for my family.  I really enjoy the people I’ve been associated with at work lo these many years.  I’m lucky to work in a business that I’m still excited about, considering I fell into it by chance.  I have my health and, God willing, will have for many more years.  I have a loving wife who has yet to come to her senses, lose her patience and throw me out.  And children now nearly raised who’ve done the one thing they could do to make up for all the times we doubted what we did in bringing them into the world:  they’ve given us grandkids.

    Which brings me to the one thing I really would like, Santa.  At Thanksgiving, I was chased and was chasing a couple of two-year-old grandkids around the house, playing hide-and-seek, peek-a-boo, etc.  Is there any way to make that pay?  I like my job and all that, but I’d really like to do that full time.

    And Santa, I know you’re good, this is one we need you to please pass upstairs to the Big Man (if He’s not already listening): never let me forget about the men and women in the military, making sure we can enjoy the bounties of this good land and this way of life.  One of them this year is ours, about to go in harm’s way.  As every parent knows, there are not enough hours in the day to plead for their protection.  Good, bad or indifferent, this is still the good ol’ US of A. I wouldn’t live anywhere else.  I’m grateful for the good blessings of this land, and the people who have died for me to be able to enjoy it.

    Never let me forget the reason for the season, that I can and should have good will toward all men, and do all I can to be of service and comfort to them all year long.  And as the boy said, “God bless us, God bless us everyone.”  Best wishes for the best of the season to you and yours, wherever you may be.  Thanks for listening.


    The Knicks.  All 18 of us (19 in June).

    PS:  Is there anything left to get the Eagles in the Super Bowl in the Cowboys’ stadium in February?  Please, just this one year, please, I’m beggin’ ya…

  • The last two blog posts focused on a host of glazing system information that can be included in BIM models. So what? What practical use does it have for glaziers? Wrapping it all up, here are some ways BIM can help streamline glaziers’ work.


    • At the click of an icon (and with the right kind of software development – this isn’t happening just ’cause an icon was clicked), a complete material list can be generated, including fasteners, glass sizes, extrusion lengths and quantities, finishing square footages (by part or in whole), etc.
    • Linked-in software can optimize material lengths.
    • Material spreadsheets can automatically be sent to suppliers for pricing.
    • Quantities for shop and field labor can either be built into the estimating software based on downloaded quantities from the BIM model, or built into the BIM models themselves.
    • Shipping and quantity weights (for extrusions, anchors, etc.) can be developed.

    Structural Engineering:

    • First, a word from our lawyers:  no engineering analysis should ever be completed without review by a licensed professional engineer (now I can sleep tonight).
    • There are third-party software applications being developed for structural engineers to work directly from BIM models.
    • Preliminary engineering analysis can be completed, optimal splice locations can be adjusted or played with to cut down on profile weights/sizes.
    • Members needing reinforcing are flagged, and various reinforcing scenarios can be analyzed for optimal cost and shop labor savings.

    Submittal and Part Drawing Engineering:

    • The BIM model acts as the real-world, 3D control for all dimensions on the project.  Elevations of the BIM model can be drawn in 2D, but the dimensional control, be it vertical or horizontal, is maintained in the BIM model.
    • On flat walls, this may not be much of an advantage.  But as more architects are drawing the windows and curtain wall in 3D, this functionality becomes critical.
    • The parts are completely modeled with all their holes, notches, preps and any and all machining in 3D or BIM.  Exporting them to a more manufacturing-friendly software environment is possible.  It may also be possible in the not too distant future to eliminate the part drawing altogether, and move the part directly from the model to the CNC machinery in the shop for fabrication.

    Production and Field Installation Crews

    • Access to the part drawing, manufacturer, or material supplier is possible once the model has been updated with the final part or mark number.
    • The user can click on a part in the model, find the length, finish, supplier of any portion, and links to the PO. In essence, the history of the part is instantly at their fingertips (or in the case of the computer, at the touch of a mouse).  No more calling back to the office.
    • Shipping info, such as when it was delivered, what crate number it was packed in, and where that crate is on the building can be added.

    For the owner and architect, the BIM model can be a useful tool for tying in maintenance schedules, product data on materials used in the project (the sealant, the glass, the finishes, etc.), ordering the correct replacement parts, be they glass or door hardware, etc.  All the manufacturing and installation information, down to the smallest screw, could be embedded in the model.

    So who pays?  It’s not yet clearly defined who will bear the costs of adding such data.  My guess is that as contracts are written and scopes of work are defined, the glazing sub is going to know or be asked to incorporate a certain level of detail for those projects whose owners choose to implement BIM.  The GSA is leading a lot of efforts to include such data in their projects, and the GCs and architects, as part of their services, are certainly going down the path towards a more robust implementation.

    What all this means to the glazing sub is hard to say.  BIM hasn’t made its way that far down the pipeline.  Yet.  There’s a couple of ways this could go:

    • The bigger glazing subcontractors are experimenting and learning the base point lessons now.  One company is doing complete turnkey curtain walls based on a fully modeled curtain wall.  All of their material procurement and engineering is based on a single 3D model, and they are doing some of the more interesting and innovative architectural projects out there.  Granted, being a large company allows the horsepower to be devoted to this, including company resources and manpower.
    • The smaller companies may look to the manufacturers as part of their engineering services to take this on.  That works to some degree, but only for the manufacturer’s operations, upstream from the glazing sub.  Nothing would be built into that BIM model that may be of value to the glazing sub, without specific agreement between manufacturer and sub.  That scenario would cut off any benefit to the glazing sub within their own operations and certainly downstream to their field crews and to the owner and/or architect as well.  The glazing sub may have to take it upon themselves to add anything they the glazing sub want to add to the model to benefit their own operations or for their downstream customers.

    Like CAD was in the ’80s, it may not be long until BIM is more readily accepted.  The initial momentum looks encouraging, and it’s going to be VERY interesting to see how all this turns out.

USGlass Magazine

USGlass Magazine