Why NFRC uses U-factors for windows

Recently, I’ve seen a number of articles, blogs and online discussions regarding U-factor and R-value, especially with regard to fenestration products. It’s time for NFRC to set the record straight on this important issue.

NFRC recognizes only U-factors for energy ratings for important technical reasons, consumer reasons and legal reasons.

This is not a simple issue. From a technical perspective, U-factor is not a material property value. It is the result of a calculation that combines the conductance values of the numerous materials in a fenestration product. This includes glazing materials, gas fills, spacer materials, framing materials, weather strips, sealants, etc. In addition, it includes the convection and radiation elements that occur within and adjacent to the fenestration product surfaces that dramatically influence its energy rating. In thermal chambers, NFRC tests products at specific environmental conditions with tightly calibrated equipment, and also applies a standardized air film coefficient to assure repetitive results from lab to lab.

The American Society of Heating, Refrigerating and Air-Conditioning Engineers has long recognized U-factor as the correct measurement for both fenestration products, and wall and roof assemblies. Only specific materials have a recognized R-value. In addition, the International Energy Conservation Code only recognizes U-factor for fenestration products. ASHRAE 90.1, for commercial buildings, and the IECC, for residential buildings, both reference NFRC’s procedure for determining the U-factor of fenestration products (NFRC 100).

As a 501(c)(3) public service organization, NFRC has an inherent responsibility to communicate to consumers, government bodies and others the most appropriate and credible information about fenestration product performance. Because U-factor provides more technically sound information for fenestration products, NFRC provides U-factors rather than R-values. U-factor is directly related to energy savings because it directly predicts reduced heat transfer. In contrast, the relationship of R-value to energy savings is more complicated and highly variable.

With the energy performance of products assuming increasing importance in today’s marketplace, fenestration product manufacturers face expanded legal risks if they advertise the energy performance of their products in an inaccurate or misleading manner. In fact, the Federal Trade Commission (FTC) has adopted regulations intended to protect consumers from misleading and deceptive advertising practices regarding R-values and home insulation products (70 Fed Reg. at 31,259). However, those regulations give no direct guidance regarding the use of R-values for fenestration products.

It is critically important that product performance is communicated consistently to all interested parties. U-factor is the recognized term for relating the thermal transmittance of windows, doors, skylights, curtain walls and fenestration attachment products. NFRC will continue to recognize U-factor – and U-factor only – for fenestration products.

--Jim Benney is the National Fenestration Rating Council’s chief executive officer. He has been involved in developing product and performance standards for the window and glass industry for more than 20 years. He can be reached at jbenney@nfrc.org.

The opinions expressed here are those of the individual author and do not necessarily reflect those of the National Glass Association, Glass Magazine editors, or other glassblog contributors.

The mental game

You’ve probably heard that “a 1000-mile journey begins with a single step.” This is true. Just as true is the fact that “the journey continues with a single step.” In previous blogs I stated that I am training to run 56 miles on my 56th birthday. Also stated were potential conflicts/obstacles that could interrupt my training.

During my training every time an obstacle has appeared, I have been faced with a choice to stop or find a way to circumvent the obstacle. What I have realized is that the challenge is not physical but mental. In fact, it really comes down to taking another single step.

At the end of March, I was scheduled to run 28 miles. I can run 1.2 miles from my house to get on the Country Music Marathon course. I pick up the course at the 6-mile point of the CMM. The course finishes at LP Field, home of the TN Titans. Counting some deviation the stadium would be 22 miles into the run. The stadium is 6 miles from my house so that would give me 28 total miles. The CMM course runs through Music Row and The Gulch areas, which are attractive interesting parts of the city. After these areas it is a very boring unattractive course. It runs by government subsidized housing and through an industrial area that borders the housing. We go briefly through a park and return to the industrialized area. When I reached LP Field (22 miles) I called my wife to come pick me up. I just quit! I was pissed but did not know why I quit. I replayed the decision to quit in my mind for several days until I determined an answer.

I discovered that I was mentally bored. My mental exhaustion led to a perceived physical exhaustion. I was at the foot of a pedestrian bridge that goes from LP Field over the Cumberland River into downtown Nashville. Downtown Nashville is an alive place with construction, the Country Music Hall of Fame, tourists and other distractions. All I had to do was take a single step to begin to cross the bridge and get into the downtown area. My brain would have been awakened and any perceived physical exhaustion would have been diminished. I would have kept running and completed the 28-mile run. But I didn’t take that step.

It wasn’t a physical reason I quit, but a mental one. The decision to quit is rarely physical; it is almost always mental. All I had to do was cross the bridge. It didn’t matter if I ran, walked or crawled over that bridge. It only mattered that I continued on my journey, took the next step and crossed the bridge. This has become my mantra. All anyone has to do to overcome an obstacle is just “cross the bridge.” In my case it was literal. In others it may be figurative.

“Just cross the bridge!”

—Bill Evans, president, Evans Glass Co., Nashville

You get what you pay for

2009 was a tough year for contract glaziers. Of the companies that made this year’s Top 50 Glaziers and provided exact sales figures for 2008 and 2009, 55 percent reported a decrease in sales volume. Glaziers cited decreased backlogs and increased competition among the reasons for the slide. Some described a bidding environment in which general contractors were “shopping numbers,” looking for the best deal. One company reported its competitor was bidding projects at cost, just to land the job.

Whether the fault lies with the clients for rewarding low bidders or with the glazing companies for submitting these bids in the first place, this type of environment is detrimental and frustrating for everyone involved.

I’m a firm believer, however, in the motto: “You get what you pay for.” And I think in the long run, our industry will actually benefit from this situation. If you’ve ever been burned by a service provider that you chose based solely on price, you know what I’m talking about. Oftentimes, it only takes one bad experience with a contractor to make you re-evaluate your selection criteria.

Companies that take jobs at unrealistic prices have to cut corners somewhere. As one glassblog reader pointed out: “If a contractor is 40 percent less than the rest, there is a reason. Material does not have that much of a swing from one guy to another, so … where are the shortcuts going to be applied?” Unfortunately, for some clients, those shortcuts are applied to the building itself, costing them more to fix than it would have to hire a higher quality company initially. Fortunately, for us, these clients will be better educated when they spec their next project, recognizing the value higher-priced companies bring to the table in the form of quality products, trained personnel and customer service.

While I don’t wish this experience on anyone, clients that look only at the bid number and not at the glazier are setting themselves up for failure. My bet is they won’t make the same mistake twice. What’s yours?

—Jenni Chase, Editor, Glass Magazine

Representation without taxation

A Census Bureau person was on the news saying that, if conservatives don't participate in the census (due to their presumed anti-government sentiment), then they will be under-represented for the next 10 years in Congress, school funding, highway funding, etc. But really, everyone feels like "their position" is under-represented, whether they are liberal or conservative. We all believe that most people should think like we do, and that the system is stacked against us (and many times there are real abuses of the system that lend credibility to our assumptions).

While the census will never eliminate this "perceived" misrepresentation, neither will it result in an accurate count upon which to base our representation for the next decade. That's because the census is about counting warm bodies without regard to their citizenship, instead of counting citizens. Take a look at the form here. There are no questions about citizenship, only ethnic origin. Now, I'm not opening the whole immigration can of worms here, I'm just saying ... if we're going to use this count to establish our representation in the United States Congress, let's base it on the number of United States citizens.

Worse yet, the Census itself is a redundancy! The IRS already knows how many people are in this country, where they live, and how much money they make. They even know my kids' names and social security numbers. So, why are we counting everybody again, with an entire separate bureaucracy? Most everybody on the IRS rolls is at least a tax-filer, even if they are not a tax-payer. This seems like a much better way to establish congressional representation -- base it on law-abiding taxpayers/tax-filers, not a head count of every warm body. The result: the end of representation without taxation. The bonus: eliminating the Census Bureau will save billions of dollars, and eliminate one little bureaucracy. We can accomplish the constitutionally required count without them.

There are two possibilities regarding my theories: they make too much sense to become government reality, or I am way off base. Honestly, it could be either. Maybe the census is a wonderful thing. What do you think of the decennial enumeration? Do you have strong feelings about completing (or not completing) yours? Have you been visited by a Census worker, and what was that like? I ended up sending mine in before they came looking for me.

--By Chris Mammen, president, M3 Glass Technologies, Irving, Texas

Avoid delays on recovery-funded projects

The glass and glazing industry is starting to see the trickle-down of government recovery money, but it is not without a price. These projects are tagged with important features that glaziers will do well to be aware of. Most of the projects are for Department of Defense installations or GSA, and have blast resistance requirements.

A significant percentage of the recovery money ends up in the hands of architectural firms responsible for design and construction oversight. The design budgets are nice and fat, and many of the architectural firms hire blast-load consultants to provide design input, write specifications and review submittals during the construction phase. So now the typical submittal has to jump through an additional hoop. The blast-load consultants are usually eager to make their value known, requiring every “t” to be crossed and every “i” to be dotted.

Sometimes, the blast-load consultants are not altogether familiar with glazing systems, and this results in a nightmare of rejections and resubmittals. Submittals that are rejected require time, effort and often a tangible dollar amount to be resubmitted.

Projects with recovery earmarks are good business when you understand their process, and glazing contractors who want to cash in on the recovery money should be prepared for the additional efforts that are now necessary. Stay tuned for my next blog, where we’ll cover some of the items typically required in submittals for blast-resistant glazing.

--By Stewart Jeske, P.E., president, JEI Structural Engineering