Friday, March 5, 2010

Using PHPP as a design tool: p.1

Here's a big question about architectural design: Should building form start with a sculptural idea/preconception about "style," or should it follow from something more rigorous?  A leading question, of course.  If only we had a tool that would provide a clear and rigorous standard whereby form could be judged by its performance...using an organic analogy, if the building were an animal, it would find the right spot on the site to suit its thermal needs, would adjust its surface-to-volume ratio accordingly (think of the cat stretched out in summer, but curled up in winter), would have an appropriate skin for the elements, and so on.  The right design tool would help determine that sweet spot for any given climate and site.

PHPP is the Passive House Planning Package, software developed by the Passivhaus Institute (see the PHIUS link on the sidebar for info),  that allows the designer to predict energy consumption, heat loss, passive solar gain, thermal bridging, and a host of factors that influence building performance.  Since 1991 the tool has been developed to provide great accuracy of prediction.  Use of the software is required to design to Passive House certification.  I bought the software shortly after attending the Passive House US Conference in October 2009, but haven't yet been able to attend a Consultant training class.

My first task with the software was to try different building configurations on my test lot--my own 30'x126' lot in Oak Park-- to see how certain design decisions would affect overall performance, especially the target of 4.75kBTU/s.f.A for space heating. 

With a tool like PHPP, the "organism's" shape, orientation, and location can be situated for its site.  The art of architecture is to tranform that high-performance shape into inspiring form, create beautiful interior spaces and natural light, and make visual and spatial connections to the outdoors.  My upcoming posts will document some of my trials.  For a teaser, here's a rendering of one of the test prototypes: