AGG
Volume 28, Issue 6 - November/December 2014

Day Planner
An Understanding of Daylighting Can Be a Value-Add and Opportunity for Contract Glaziers

By Ellen Rogers

Daylighting Design Components
According to the Whole Building Design Guide, “daylighting design is not just how to provide enough daylight to an occupied space, but how to do so without any undesirable side effects. Beyond adding windows or skylights to a space, it involves carefully balancing heat gain and loss, glare control, and variations in daylight availability.” Considerations often include the use of shading devices to reduce glare in the workspace, as well as window size and spacing, glass selection, and more.

Glare isn’t a four-letter word, but it might as well be. Ask anyone who has suffered a glare-ridden interior space, so much that they found themselves wearing sunglasses simply to see the computer screen, and they may have a few choice words to say about it. So what happens? The blinds come down, the curtains are closed, the lights go on—and the energy bills go up. But all hope is not lost.

That’s where daylighting can help. What exactly is daylighting, you may wonder? Letting light inside a room? Installing a skylight and adding a few extra windows? While true these all allow daylight inside, yet the act of daylighting is quite a bit more complex. According to an article by Gregg D. Ander, FAIA Southern California Edison, on the Whole Building Design Guide website, “Daylighting is the controlled admission of natural light, direct sunlight … into a building to reduce electric lighting and saving energy. By providing a direct link to the dynamic and perpetually evolving patterns of outdoor illumination, daylighting helps create a visually stimulating and productive environment for building occupants, while reducing as much as one-third of total building energy costs.” Did you get that part: reducing as much as one-third of total building energy costs. In other words, you can’t just install a window with clear, single-pane glass and call it daylighting. Sure the room will be bright, but the energy bills will be outrageous. Add don’t forget: glare.

But what if an architect, in his or her desire to practice a “daylighting design,” specifies an inappropriate glass type or window system? Chances are that, at some point, the building owner will be faced with unhappy occupants who are sweating from the heat and shielding their eyes from the glare. No one will be happy.

“You can’t just put windows in and call the building daylit.  A lot of thought has to go into controlling the negative impacts of the heat that comes in with it and the glare,” says Helen Sanders, vice president, technical business development with SageGlass in Faribault, Minn. Sanders, along with Pekka Hakkarainen, vice president of Lutron Electronics in Coopersburg, Pa., led a discussion about integrated daylighting design during the GlassCon Global Conference, held in July in Philadelphia. “ If this is not done the daylight design will be ineffective—it will be uncomfortable and the benefits of daylight will be negated because occupants will pull blinds or put paper up on windows, etc. which stays in place long after the glare condition has gone, negating any of the benefits of the daylight design.”

Contract glaziers, however, have an opportunity to help. Those who are aware of daylighting design principles and understand which products are best to use and the locations and regions in which they should be used can play an integral role on the design team—now as well as on future projects.

Why Glaziers Matter

At first thought, the subject of daylighting might not seem as pertinent to the contract glazing field as it is to the architectural community. But it is.

“If glaziers understand the basics of daylighting, they can provide effective input and solutions to the design team early on in the design process and help to head off problems of glare and too much heat gain down the road,” says Sanders. “It might help the contract glaziers be a valued seat at the table with the design team if they understand what the team is trying to do and have the tools to help them achieve it.”

She continues, “They also have the knowledge to counter the arguments to ‘reduce window area’ to minimize building energy usage and provide alternative solutions.”

Alana Griffith, vice president of Empirehouse Inc., a contract glazier in St. Paul, Minn., says that not understanding daylighting criteria can also have negative outcomes after completion —particularly if a contract glazier was involved with a poorly designed building or one where glazing products were changed during a value engineering process.

“It reflects negatively on the glazing contractor,” she says and gives an example of a project in which the building owner immediately added window blinds to the openings to protect from excessive light, thinking, “I hate these new windows.”

“They don’t hate the windows; they hate the glare. When the owner or building manager looks into the project’s closeout documents, they can find information on the glazing contractor and material sources, and the connection is made. When something goes wrong … we’re the ones first suspected as being at fault.”

Marty Richardson, sales manager with Metropolitan Glass in Denver, agrees.

“Contract glaziers can only fall back on what experience they have in the past,” he says. “If you can talk with the architects about what you know and make suggestions about light transmittance, for example, without committing to being engineer or designer, you can help [guide them], but you need the knowledge to talk intelligently.”

Use Your Resources

Suppliers can also be helpful in providing education. Richardson said one of his company’s glass fabricator representatives once organized a walking tour of downtown Denver in which he discussed daylighting designs.

“It’s good to have as much knowledge on every aspect of the trade as possible,” says Richardson. “General contractors look to us to be the experts in what we do; they can’t quantify glass because there are so many variables unlike concrete, carpeting, etc.”

Likewise, Rich Porayko, who works in marketing for Seattle-based Hartung Glass Industries, says his company collaborates with contract glaziers on daylighting, along with the architect, “to find the optimal insulting glass unit makeup to maximize daylighting without glare or unwanted solar heat gain.” He says this is often achieved through the use of a solar control frit pattern or sunshades.

What to Know

According to Griffith, her company is often involved early in the design phase on a design-assist basis. As a result, she says her team members are able to talk about the issue of daylighting upfront with the architects.

“Many glaziers contractors won’t question a specification, and will provide exactly what is written rather than asking during the bidding phase, ‘is that what you really want?’” she says. “If we see issues or potential problems, we frequently ask questions of the architect to find out exactly what they are trying to achieve. Especially when the engineers have not been brought in early in the game, the design team may not specifically know what comfort level or performance they should design to. Spending time at this phase could greatly impact the life cycle cost of the building, she suggests. “After the building is complete, do owners want to unnecessarily add the cost of shades and blinds, which will be replaced multiple times over the life of the building? Or, would they consider different glazing solutions that would provide many years of service? Looking at the larger picture of proper daylighting can help the owner, building and design team make better informed choices during the initial construction phase.”

Porayko adds, “There are over a billion ways to fill a hole in the wall. Quite often, the architect and contract glazier know exactly what they are looking for. Other times there is an extensive sample or mock-up process in which we will work with all of the project stakeholders from the municipal government to the primary manufacturers to get the optimal performance of what the architect wants to achieve.”

A Part of the Team

From energy savings to interior comfort, daylighting is a design practice that can bring multiple benefits to both building owners as well as occupants. It also provides an opportunity for those involved with the project to explore new technologies and innovations, which, in the end, they can also offer their customers.

“Daylighting is a growing trend. High performance low-E, solar tubes, solar control frit patterns, sunshades and light shelves are just some of the current techniques being used,” says Porayko, adding that both thermochromic and electrochromic glass products are quickly becoming more cost effective, “which will add a whole new dynamic to daylighting.”

However, despite the fact that there are so many new and emerging products, Griffith adds that becoming more involved on projects is also important.

“Glaziers may not be aware of how valuable they are as resources to the architectural team. The designer has countless materials and product details to be responsible for on the project. They need our expertise to make informed and proper decisions.”  She encourages all glazing contractors to “[work to] become an important and valued construction team member and not just another sub.”

Metropolitan Glass installed curtainwall on the south-facing façade of the Denver Museum of Nature & Science, which was designed with daylighting in mind.
AGG



Ellen Rogers is the editor for Architect’s Guide to Glass and Metal magazine. She can be reached at erogers@glass.com




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