Change The World 2008

Change the World 2008:
Harnessing BIM Technology and Integrated Project Delivery for Sustainable Design

Change The World 2008

A pre-convention to the AIA National Convention next week in Boston will be taking place on the 13th and 14th. I'll be blogging LIVE about the sessions I attend, so stop by and throw in your 2 cents if you have a chance.

Glass Boxes in Hot Climates

"Don't expect comfort inside glass boxes in hot climates" are words from The ASHRAE Guide for Buildings in Hot and Humid Climates. Shading the roof and other badly oriented surfaces is imperative, but you have to address the fact that heat is rapidly entering the space due to the high thermal conductance of glass. The obvious recommendation is to increase the percentage of solid to glass surfaces.

But once you've blocked the direct solar, how much glass is still too much for conduction gains...

Background: Introduction

Green BIM Network is a collaborative movement in the building industry which started as a simple workshop in Washington DC where Architects and Engineers can pool their expertise and ingenuity to pioneer environmental and performance analysis integrated with Building Information Modelling. This blog page will be a recorded document of all efforts either locally or across the web. Postings will be divided into one of five categories:

• Background Information / Editorials
• Forums / Open Ended Problems
• Case Studies /Solution
• Controversies / Challenging Debates
• News / Current Events

Welcome to our forum, please contribute where you are able.

Lighting vs Energy Model

I'm just going to throw this out there; someone needs to own every analysis model and develop a method for keeping it current.
Working with Revit, my belief is that the Architect should own the daylighting model which can be exported either through room objects or BIM geometry. Room objects are the best candidate in that they often describe only those areas that need to be analyzed.
IES daylighting Image courtesy of RTKL











The energy model intended for thermal analysis is best created in Revit MEP using space objects. Space object can be placed into a linked Revit file in Revit MEP, but the must follow the room bounding rules set by the Revit architecture model. To get around this, spaces can be grouped together into zones for analysis, and a sliver tolerance can be adjusted so that leftover gaps don't require space definitions. We now just need to test how effective zones are and if there is an additional performance drain by having many small spaces which the energy modeller would not normally define (this will come in a separate post).

Added Later:

After some discussions I'm rethinking the concept that the Architect always owns the daylighting model. The architect needs to start a daylighting model to reveal problems while they can still be solved schematically. The big danger in Daylighting analysis, as described to me by Chris Chatto of ZGF Architects, is that the end result needs to be a value, either a 2% daylight factor or the 25 footcandle (269 lux) requirement for LEED EQ 8.1. In this case the analysis iterations are not intended to improve a design but to achieve levels above a defined value.



Without carefully defining all of the input parameters such as glass transparency, reflectance of materials, sky condition and others, one could seemingly prove that a design is adequate when in reality it is not.




This level of daylight understanding is not always present in every architecture office and so a level of collaboration becomes necessary. Who actually "owns" this model may end up an irrelevant question, but before deciding a model exchange strategy you have to know exact procedures and what to expect.




Ecotect to IES Exchange

I've mostly been using Ecotect as a design analysis tool, and since the engineers I work with are mostly using IES for lighting calculations I've had to find a clean way to exchange information between the BIM model, the design analysis and the engineering analysis tools (this process will come in a later post).

PreDesign Analysis with Cylinders and Spheres

Imagine having a simple chart that can allow you to make nearly every orientation design decision with the confidence of comparing numbers. Some might call it cheating to not fully investigate all of the factors involved, but if you don't have the capability to conduct a full thermal analysis here is a quick way to make informed decisions.

But there will always be designers who simply avoid problems with numbers, for whom these tables might not be clear enough. Since I have nothing to gain by letting buildings fail I've found a way to make this process more user friendly, and more convincing I hope:

Using Ecotect I created a simple cylinder faceted into 360 surfaces. I placed my shape in a hot climate where several HOK projects are located and and then ran a quick insolation (also known as Incident Solar Radiation, the cause of solar heat gain) analysis for the course of the year. From these results I can now tell exactly the amount of solar radiation is will reach any unobstructed vertical surface in the project.

Now we have a choice to look at the numbers or colors.

For those not designing vertical walls, now you can now incline with a purpose.

The First Tenet of Green BIM

The first fundamental of an iterative Green BIM process is the necessity for integrated 3D design. Alternative workflows will ultimately lead to a clumsy process of redrawing, working backwards, and constantly fighting deadlines with an inefficient use of resources. To be very clear about what I'm saying, a design or changes to a design can begin with a sketch, but every move thereafter must first be made first to the BIM model...the model must always be the most up-to-date file in the project folder.

Bahrain Water Gardens - a successful BIM design and analysis process.

When a designer insists upon working in a non-BIM system it is imperative that any presentation drawings must first go through the BIM application before the date of submission. If the project team has to rely on a process of continually revising the analysis model post deadline, no progress can be made and the iterative analysis will disappear from the process.



Bahrain Water Gardens - every design decision is validated by instant analysis

An Evolved Architectural Philosphy of Progress

This Editorial is dedicated to what I believe are the supporting philosophies of Sustainable Building Information Modelling as a continuity of 19th and 20th Century Modernism ideals deriving from and celebrating honesty and spirit

MODERN ARCHITECTURE: L'ESPRIT NOUVEAU

Immeubles Villas by Le Corbusier

Twentieth century Modern Architecture sought to replace archaic building practices with modern methods and vigor --L'Esprit Nouveau was a positive answer for postwar rebuilding. What crossed the Atlantic was little more than fragmented commercial imagery where structure became ornament, Kernform became Kunstform. After the brief rise and fall of Postmodernism in America we are now finally discovering that Modern architecture never died but continued elsewhere, evolving into a variety of forms before reimerging in America as purpose driven sustainable design.
The first great mistake of our Modern predecessors was allowing a movement born out of genuine purpose to reduce to an aesthetic style. To prevent this history from repeating we should seize the opportunity to integrate analysis technology as an informative design tool, second only to our spirit.

HIGH-TECH SUSTAINABLE MODERNISM: THE EVOLUTION

A green office building by Future Systems

High-tech Sustainable Modernism, or what may ultimately be called High Modernism (in preference to the clumsy phrase "bionic architecture") has now had several generations of refinement and is today more exciting then ever. Twentieth century modern architects left a trail of many unfortunate failures in North America. Designing without precedent was a new found freedom for designers that often became a burden upon society. This, the second mistake of modern architects was made by those individuals who strictly favored "a priori" rather than "a posteriori," or the predictable knowledge ahead of the experienced. Their methods of analysis were particularly weak and they placed no value on the trial and error process to learn from others mistakes.

Today when introducing new building types and construction methods into any region of the globe it is imperative that we utilize analysis technology, not merely to predict energy consumption but to iteratively refine the design performance. This method of gaining knowledge through simulated experience has greatly benefited the automotive and aerospace industries and is about to revolutionize the building industry.

FORM FOLLOWS PERFORMANCE

Concept for an off-grid office building

The collaborative approach for analysis and design works to replace intuition with iteration. Experienced iterative analysis as a design tool follows a natural process for a refinement of design performance. The ideal of Modernism that Form Follows Function mislead generations who confused economy and spatial convenience for inherent purpose, or purposiveness of form. Form Follows Performance tells the philosophy in a manner which cannot be misconstrued, which must lead ultimately to our goals of Green Living in a world of rapid urbanization.

GEOMETRY OF NATURE
Studies of bifurcations approaching turbulent behavior

Often forgotten were the movements and many individuals throughout Modernism who looked to nature to guide designs related to structure, form, and ornament. From Viollet-le-Duc, Gaudi, Wright and Aalto, to current innovators such as Norman Foster and Future Systems, the influence of nature on modern architecture has been profound. It is worth noting that these architects focused also on the interactions between the user and the natural environment, and on the performance of the building. Holistic design inspired by and venerating nature is today termed Biomimicry.

COLLABORATIVE PROCESS

The drive for a competitive edge needs to be redirected towards the larger enemies chipping away at climate stability. If one is passionate about sustainable design they cannot simultaneously wish to see competing firms or countries producing an inadequate shared environment. The Green BIM Network is a pure collaboration of environmentalist architects and engineers. There is no hidden agenda but the desire to be a part of a cause that will make future generations proud, and for each of us the confidence to look in the mirror at the end of the day and know that we've contributed.