# Buildings with solid glass exteriors



## -KwK345- (May 23, 2007)

Are buildings with solid glass exteriors harder to heat and cool, or no because the glass can be tinted and double painted? If they are harder to heat and cool, why are so many buildings built like that today? Can you make a building look as if it has a glass glaze but actually have the inside walls not be walls of windows???


----------



## Indictable (Sep 23, 2008)

these are definatly my favourite type of office buildings.. glass =D


----------



## Homer J. Simpson (Dec 2, 2003)

Royal Bank Plaza are all glass buildings. Their glass is processed with real gold that gives it a highly reflective surface that reflects light keeping them cooler in summer than normal glass buildings.


----------



## -KwK345- (May 23, 2007)

Indictable said:


> these are definatly my favourite type of office buildings.. glass =D


Same here!


----------



## Slartibartfas (Aug 15, 2006)

-KwK345- said:


> Are buildings with solid glass exteriors harder to heat and cool, or no because the glass can be tinted and double painted? If they are harder to heat and cool, why are so many buildings built like that today? Can you make a building look as if it has a glass glaze but actually have the inside walls not be walls of windows???


The German Darmstädter Instituts für Wohnen und Umwelt had a look into this issue once if I remember correctly.They managed to get the numbers of the real energy consumption of 24 glas style skyscrapers. The result was that the amount of energy needed to run them was nearly obscene in its dimensions. You may say as energy efficient as a Hummer car. Which leads us to your other question, why do people buy Hummers for city traffic purposes? Its damn sure not to save energy.

The average of energy consumption of glass style skyscrapers was 300 to 700 kWh/m2. Stone facade buildings feature a consumption of 100 to 150 kWh/m2. That should make clear how much of a waste of energy it is. Even if you calculate an error meassure due to higher consumption because of IT facilities etc in, they still would need not above 300 kWh/m2.


----------



## -KwK345- (May 23, 2007)

but aren't a lot of glass buildings green or can they be green by the use of renewable energy and solar panel stuff?


----------



## Slartibartfas (Aug 15, 2006)

-KwK345- said:


> but aren't a lot of glass buildings green or can they be green by the use of renewable energy and solar panel stuff?


No they might be cool looking and representative etc but they hardly are green. That does not mean that one could improve the energy efficiency of glass buildings a well, even substantially. As of today stone buildings have a large advantage in energy efficiency however. The main problem with glass towers is overheating, the worst of them have to be _cooled_ even during winter. There is still no mature system out there to counter that problem.

BtwI would be the first to be enthusiastic if glass towers would go green, as I think they are cool looking often enough. But until they don't tackle this problem reliably I can't be a huge fan of them.


----------



## -KwK345- (May 23, 2007)

well some people say they can be green, and some say no. Who do I believe?
Aren't most green buildings glassy? Even if a building with a solid glass exterior can't be green or energy efficient, don't most zero energy buildings have a lot of windows?


----------



## spongeg (May 1, 2006)

the term "green" is too loose and the criteria flucuates too much to be a standard

does making a green roof really make the building that much better?

sort of like Organic - it can be slapped on loads of products but what does it mean - for the most part organic food and such is not regulated so there is no real control or standard for it to qualify as organic yet people say its "organic"


----------



## Annibale (Dec 30, 2006)

-KwK345- said:


> well some people say they can be green, and some say no. Who do I believe?


Glass glazed buildangs can be green only with active systems. They produce energy (solar panels etc...), save energy with some solutions (radiant panels, heat pumps), while sucking a lot of energy for heating or cooling.
Aren't most green buildings glassy? Even if a building with a solid glass exterior can't be green or energy efficient, don't most zero energy buildings have a lot of windows?[/QUOTE]

Maybe it's because most of the energy efficient buildings you've seen are from northern Europe. With such climate, buildings need south oriented windows to catch incoming solar heat (especially in office buildings, houses need more thermal capacity to release the heat during the night, and thus more walls).
If you consider a hot dry climate, like northern Mexico or the middle east, the best building has thick walls, little windows, maybe an inner court and other elements...


----------



## -KwK345- (May 23, 2007)

All I know is that almost all the green buildings I've seen in photos are glassy (and no they are not in all Northern Europe). Take for example the new Bank of America Tower in NY. It is glassy and was named the greenest skyscraper in the world. It is said to have glass that minimizes solar heat gain while maximizing daytime light. And look what this says: http://www.visionwall.com/Html Files/featuresbenefits.htm


----------



## Slartibartfas (Aug 15, 2006)

-KwK345- said:


> well some people say they can be green, and some say no. Who do I believe?
> Aren't most green buildings glassy? Even if a building with a solid glass exterior can't be green or energy efficient, don't most zero energy buildings have a lot of windows?


"Green buildings" feature glass intelligently, ie they have exactly as much glass as needed to maintain the best temperature over the year with the least energy imput. Thats something entirely different then the randomly usage of glass in glass-skyscrapers, where far too much glass is use and the buildings have to be cooled down with an extreme amount of energy.

Its true howver that the are attempts to make those skyscrapers greener, but all efforts have not resulted in reliable and satisfactory results so far.


----------



## Slartibartfas (Aug 15, 2006)

spongeg said:


> the term "green" is too loose and the criteria flucuates too much to be a standard
> 
> does making a green roof really make the building that much better?
> 
> sort of like Organic - it can be slapped on loads of products but what does it mean - for the most part organic food and such is not regulated so there is no real control or standard for it to qualify as organic yet people say its "organic"


I agree that "green" is a very vague term. "Organic" is however not, at least in Europe. If you want to label something as organic you oblige yourself to strict rules and tight regular controls. Thats the case for everything sold in the EU as organic. Organic therefore is a clear standard and obligatory includes strict controls, as I have said though, at least in Europe.


----------



## Slartibartfas (Aug 15, 2006)

-KwK345- said:


> All I know is that almost all the green buildings I've seen in photos are glassy (and no they are not in all Northern Europe). Take for example the new Bank of America Tower in NY. It is glassy and was named the greenest skyscraper in the world. It is said to have glass that minimizes solar heat gain while maximizing daytime light. And look what this says: http://www.visionwall.com/Html Files/featuresbenefits.htm


I don't trust that "green" label a second before the owners do not publish real energy consumption numbers of the building in kwh/m2. And I am talking about the real energy needed not reduced by potentially alternative energy produced in the building.


----------



## Manila-X (Jul 28, 2005)

Almost every major commercial skyscraper in HK are glass-cased


----------



## agentyumi (Aug 28, 2008)

I talked with an architecture regarding glass in constructing a building. He told me that glass is a superb material for thermal insulation, water proofing and energy conservation. Glass is also bad conductor of heat; it saves energy in air conditioning of building. I saw also a house which is made of glass, it’s so spectacular! Even the stairways are made of glass.


----------



## -KwK345- (May 23, 2007)

Omg everyone is saying something different. I don't know what to think!!!!


----------



## Annibale (Dec 30, 2006)

agentyumi said:


> glass is a superb material for thermal insulation


false


----------



## -KwK345- (May 23, 2007)

Annibale said:


> false


how do you know?


----------



## -KwK345- (May 23, 2007)

So are y'all just saying that a glassy building can be green but a building not all made of glass is greenER? Can you have solid insulated walls with glazed glass in front of it to give the building the glassy look? Are there any buildings like this?


----------



## gladisimo (Dec 11, 2006)

Green is a relative term. A glass building can be relatively green if designed to reflect radiation to keep the building warm/cool, combined with solar panels to make it more self-sustaining.

I don't know what having heavy materials in the construction of very tall buildings have on the load of the building, though.

Glass is typically considered a poor insulator because it lets light (EM radiation) through, and is thinner, and thus doesn't insulate well. However, double glazing (or triple glazing) forms a pocket of air, or sometimes vacuum, to insulate the glass, and various coatings can minimize the amount of IR and UV radiation that passes through the glass in order to maximize its benefit, which is to allow light in.


----------



## Annibale (Dec 30, 2006)

-KwK345- said:


> how do you know?


Thermic transmittance (the lower, the more insulated), in W / m2 K

one of the best windows *0.8* (triple glass filled with kripton, one clear glass and two low emitting glass, quite expansive, in terms of price and energy to make it)

a common masonry wall with 5cm of EPS (polisitrene) *0.47*

an average double glass window *2.9*

a 30cm masonry wall without EPS and with plaster *1.73*

Of course not only insulation matters...


----------



## -KwK345- (May 23, 2007)

so now you are saying glass is good?! OMG im so confused!


----------



## Homer J. Simpson (Dec 2, 2003)

^What he is saying is that the best window is approximately half as effective as a wall made of masonry with 5CM or about 2-3 inches of insulation.

His figures also indicate that the double pain windows in my house are aproximately 5 times less effective as the masonry and insulation.


----------

