Casa Luca

Passive House design from an architectural perspective

Too often we equate energy efficiency with sustainability, overlooking considerations of  form and design. I was interested to explore how a structure designed to meet the rigorous standards of Passive House [PH] modelling differs from any other.

BY L UCIO PICCIANO

The answer becomes clearer as one closely models a building for passive solar gain, ventilation, area/volume ratio, and thermal bridging. These considerations become the drivers of building orientation, massing, fenestration and envelope design.There seems to be an industry gap between the technical issues involved with true energy efficiency and good architectural design.

How do we achieve both in equal measure? As an architect who has always had a deep interest in elegant contextually-appropriate design combined with energy efficiency and ethical building I wanted to answer this question as definitively as possible.

Casa Luca was my first attempt at not just speculating about the relationship between energy efficiency and context, but actually calculating it scientifically. Herein lies the major difference between the PH approach and most other sustainability models.

PH modelling requires rigorous and exact dimensioning of all relevant details, components, and systems within a building. These aspects are then scientifically combined and calculated to show actual performance based on your design, precise  geographic location, and orientation.

Some constraints on design are generic for all PH projects. Working through the PH methodology, it quickly becomes apparent how adding a certain window here, or there, affects all aspects of performance. Similarly, we soon see how it is not so easy to provide overhangs and at the same time reduce thermal bridging.

Other factors may be site specific. Casa Luca sits on the south side of an east-west street in a part of Vancouver that enjoys mountain views to the north. To achieve PH performance,, one must consider these views less, instead favouring solar gain to the south. By adding roof top decks we can take advantage of north views and not affect the energy performance, this also serves as a great private outdoor space removed from the street.

There are also programmatic questions to be answered. What is the optimal location for a child’s bedroom? The kitchen? The Laundry room, and can I hang my clothes to dry in this location or do I always have to use the dryer? These are now questions that have environmental implications and are quantifiable. Architectural excesses  can clearly be seen as such.

Lucio Picciano Architect, AIBC LEED is principal of dlp architecture inc. in Vancouver. www.dlpdesigns.com

  • PROJECT CREDITS
    ARCHITECT Lucio Picciano
    BUILDING CONTRACTOR Lucio Picciano
    PHOTOS Mike O’Hanley, Barn Owl Photography
  • MATERIALS
    – Wood-frame construction with engineered roof and floor joists, and rim boards; western red cedar, metal and composite panel siding
    – Mineral wool roof insulation and exterior board insulation, closed cell Polarfoam PF7300 polyurethane spray foam insulation by Demilec
    Euroline 4700 Series Passive House [PH] certified windows
    – ERV Paul Novus 300 energy recovery ventilator by Zehnder America
    – 3KW photovoltaic array on upper roof
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