Dual Skin Facade Design: Advantages & Challenges

[banfillb]

Hey All,

Im creating this thread to share some of the information, and hopefully gain some information on dual skin walls.

Dual skin walls are a fairly new advancement in facade design in North America, however they are more common in Europe. The first dual skin facade in North America was the Occidental Chemical Center (Hooker Building) in Niagara Falls, New York, in 1980. Since then, the desire for dual skin facades has nearly been non existent. Jump forward 30+ years, and we find ourselves in the era of green buildings and construction. The desire for dual skin walls is becoming more prominent in NA, and as mentioned has already arrived in the EU.

The literature on DSF's is tough to sift through. Many attempts have been made to construct dual skin walls, but without adequate modelling software, and education on integration, many problems can be experienced. This is evident with the aforementioned Hoover building. The Hoover building has experienced many problems, which in my opinion, are due to failed maintenance and lack of technology/ knowledge on the many variables that need to be considered while designing a DSF. This is not to downplay the engineers and designers for the Hoover building, its just that the information and technology was not there 30 years ago. I will attach the article which I'm referencing.

Now that the technology, and drive for DSF's is there, a wave of opportunities and research is beginning to form. Its a very exciting concept, and right now the sky is the limit. Hopefully we can all gain and share some knowledge on the subject, and get closer to DSF's reaching their full potential.

 

[banfillb]

Couldn't attach the PDF for the Hooker building article, so here is the link:

http://www.architecture.uwaterloo.ca/faculty_projects/terri/ds/hooker.pdf

 

[Danger]

With no offense intended, it seems to me that a lot of equally/more efficient approaches are available. I can see the reasoning behind it, but have a bit of trouble believing that it can be so much more efficient than photoreactive double-pane windows and solar heating as to make it practical. I'm not denying; only doubting. I'll be overjoyed if you can provide specifics as to energy consumption vs the technologies that I mentioned, and will become an advocate. I have no brand loyalty or political or financial stake in any of this; I just don't want to back something that isn't the best available. If you have it, I'm with you. Prove it, though.

 

[banfillb]

No offense taken Danger. This is what I created this thread for.

First of all, I am not denying that both methods you mentioned are feasible solutions for energy savings, I think it comes down to the desired applications.

I need to look more into the methods you mentioned in order to be able to compare the ideas. Its also hard to find solid numerical evidence for DSF's, because they are constantly evolving and improving, like any new technology. I will spend some time today looking up some case studies to post.

From what I understand about photoreactive windows is that, they change tint depending on the level of sunlight present correct? And much like a tinted window on a car, photoreactive windows block UV light by not Infrared light? I may be out of line with this explanation, as I mentioned I am not very educated on the subject. If I am correct however, I have two points for DSF's in response to this.

1) DSF's aim to redirect sunlight, not block it. This is usually done with operable sun shades. DSF's allow for operable sunshades to be placed at higher altitudes, without a risk of wind damage. These sunshades can be controlled manually, or automatically either through a schedule or BMS (building management system). Again, it comes down to what the application is...do you want to tint the windows and block sunlight, or maintain natural lighting while also mitigating discomfort.

2) DSF's reduce heat transfer and heat absorption. Again, sunshades, and low emissivity coatings on the glass help reduce the amount of infrared heat which enters a building. The thermal emissivity values can be greatly reduced with the addition of a single pane of glass, thus creating a DSF, and the added air gap. Another benefit for reducing solar emissivity is the flow of air from bottom to top, created by the stack effect. This flow of air causes some of the heat being transferred from the exterior to the interior to be "carried" away.

Again, I do not refute that the two alternative methods you mentioned are any less plausible then DSF's, I feel it all depends on the desired application. And I could be wrong about my arguments on photoreactive windows, again because I am not as educated as some others on the subject.

 

[Danger]

I just caught this thread again, and you make some good points. I have responses, which do not undermine your approach, but at the moment I'm a little too into my cups. If I had read this when I had consumed only a dozen or so beers, I'd be okay to respond. As it is, though, I respectfully request that you wait until tomorrow (or whenever I wake up).
The two things that I will mention are that I thought that regular glass won't pass IR. I've never been able to get my TV remote to work through a window, so I figured that it was the glass causing the blockage. That might very well be a misconception on my part.
The other thing is that you mention re-directing the sunlight, which brings to mind that the redirection could be toward water heaters, room heaters, some things that I can't mention in public, auxiliary (or even primary) lighting...
I'm starting to like your approach even more as I think of it, but I'm still too drunk to make a decent post about it. I'll get back to you tomorrow or, as I said previously, whenever I wake up.