Tag Archives: windows

Thermographic Infrared Maps

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by video • Tags: , , , , , , , , , , , ,

A program in Belgium is using aerial thermographic infrared maps of neighborhoods to give folks a contextual sense of their home’s heat loss. On the image above, the blue homes are losing much less heat than the red ones and are better insulated. Viewing this kind of map gives folks a sense of how their home’s insulation levels compare to that of their neighbor’s home.

You can click the image above to watch the video (it will take you to another page), or watch it here. Unfortunately, you will have to watch a brief ad before you can see the video clip.

This post is part of our Friday video series.

Historic Vote by US Building Officials

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by current events • Tags: , , , , , , , , , , , , , , , , , , ,

Reuters reports that US building officials nationwide have voted to support the first building codes that require 30 percent more efficient buildings for every state under the 2012 International Energy Conservation Code.

Delegates also voted to eliminate the weaker Energy Chapter of the International Residential Code, supplanting it with a single nationwide uniform energy code for residential and commercial buildings.

Although some states, like California, have long had energy efficiency requirements in building codes, with a resulting flat-lining in home energy use in the state since the 1970s (to about half the average US use) most states have little or no requirements for reducing energy use. The International code has been the lowest common denominator; compelling safety, but little else in building codes. The minimum standards allowed energy to be wasted in heating and cooling homes in non compliant states by not requiring weather tight walls, roofs, windows or doors.

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“It is notable that the votes that will have the most profound impact on national energy and environmental policy this year weren’t held in Washington or a state capital, but by governmental officials assembled by the International Code Council (ICC) in Charlotte, NC,” said William Fay, Executive Director of the Energy Efficient Codes Coalition.

You can read the entire article here.

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Death Rays

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by energy, links • Tags: , , , , , , , , , , , , , , , , , , , , , , , ,

So… what on earth does this blog have to do with death rays?!

Well, yesterday the story of the “Vdara Death Rays” flew through a couple building science mailing lists that I am on. Basically, the building designers put very reflective glass on the outside of a curved building, which wound up posing a problem for folks at a pool nearby (more  below).  However, it turns out that a building doesn’t have to be curved for highly reflective glazing to pose a hazard to nearby people or nearby buildings.

How does this fit into concerns about energy use? One of the reasons that the highly reflective glazing is used is to prevent heat gain and therefore reduce the amount of energy needed to keep a building cool.

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Image credit: Wikimedia Commons

The Las Vegas Review-Journal published a story a few days ago about the Vdara Hotel on the Strip in Las Vegas.

The tall, sleek, curving Vdara Hotel at CityCenter on the Strip is a thing of beauty. But the south-facing tower is also a collector and bouncer of sun rays, which — if you’re at the hotel’s swimming pool at the wrong time of day and season — can singe your hair and melt your plastic drink cups and shopping bags.

Hotel pool employees call the phenomenon the “Vdara death ray.” A spokesman for MGM Resorts International, which owns Vdara, said he prefers the term “hot spot” or “solar convergence” to describe it. He went on to say that designers are already working with resort staff to come up with solutions.

You can read the entire story here.

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Image credit: Wikimedia Commons

In Los Angeles, Walt Disney Concert Hall, by famous architect Frank Gehry, has had complaints about glare off the reflective surfaces.

While most of the building’s exterior was designed with stainless steel given a matte finish, the Founders Room and Children’s Amphitheater were designed with highly polished mirror-like panels. The reflective qualities of the surface were amplified by the concave sections of the Founders Room walls. Some residents of the neighboring condominiums suffered glare caused by sunlight that was reflected off these surfaces and concentrated in a manner similar to a parabolic mirror. The resulting heat made some rooms of nearby condominiums unbearably warm, caused the air-conditioning costs of these residents to skyrocket and created hot spots on adjacent sidewalks of as much as 60 °C (140 °F). After complaints from neighboring buildings and residents, the owners asked Gehry Partners to come up with a solution. Their response was a computer analysis of the building’s surfaces identifying the offending panels. In 2005 these were dulled by lightly sanding the panels to eliminate unwanted glare.

Frank Gehry had this to say when asked about potential for glare on a newer LA project (via the LA Times):

I had some bum rap at Disney Hall because of glare. That was 2% of the building had reflective stuff, and some pissed off lady (complained). So the County had to respond. (It took) A couple guys with steel wool and in about an hour and a half they fixed it. But it did appear as one of the 10 engineering disasters in the last ten years—talk about exaggerating. The county did a study of downtown LA that found 5 other buildings that were more reflective, but no one complained about them. So, we got to get more pissed off ladies.

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It has also been reported in Green Building Advisor that reflections from windows can melt residential vinyl siding.

Glass experts and home inspectors agree on one point: since vinyl siding can be melted by reflectance from conventional clear glass, a low-e window is not required… However, the use of low-e (or low-solar-gain) glass appears to increase the risk of melted siding. According to an article in the March 2007 issue of USGlass Magazine, “A study performed by Cardinal on this topic examined the impact of reflective coatings on this type of [vinyl siding] damage. ‘The more reflective coatings that are out there today, that are getting more popular, are going to create this problem,’ [Jeff Haberer] said. However, Cardinal found that even clear glass can become a significant heat source.”

Glass with a low solar heat-gain coefficient has a high solar reflectance. “What we are getting is very, very good windows,” said Jim Petersen, the director of R&D at Pulte Homes. “Now the energy that is not getting in the house has to go somewhere, and it’s being reflected.”

Read the entire story here.

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