Mike Duclos – July 25, 2014 My BuildingEnergy Masters Series course, Passive House Design, is coming up in a little over a month. I want to share a sample of what we’ll be working with in the course, and how you’ll be able to use what you’ve learned to use Passive House Planning Package to get your project to Passive House (or close enough.) So, what are we looking at here?
The long elevation of the home faces close to due South, providing more wall area for windows. Slab on grade provides thermal energy storage for better thermal consistency management. Facing directly South both optimized gains and facilitates solar gain control by fixed overhang shading mechanisms.
Slab on grade construction provides a more even temperature during times of high solar gains.
‘Aging in place’ was a design goal, so living entirely on the first floor is possible.
Four bedrooms were requested to accommodate visiting family, with an open kitchen/living/dining area for entertaining large gatherings.
First floor bath, bedroom #2 walk in closet are located to facilitate elimination of North facing windows to reduce heat loss.
All bedrooms have at least two windows on different walls, to facilitate ‘windows open’ cross ventilation, as calculated via the Passive House Planning Package spreadsheet tab SummVent.
Main living space accesses views to the South, and will be somewhat warmer than rear bedrooms due to solar gains.
Point source heating efficacy is optimized by use of a central great room in which a single, 9 KBtu/Hr ductless mini-split is used for all 1st floor space conditioning, with a second unit above the first to second floor stairs landing. Experience has demonstrated that in a two story building, either heating or cooling comfort is compromised without a ductless mini-split per floor. If ductless units were undesirable, a single ducted unit could be installed in the mechanicals closet to serve both floors adequately.
The mechanicals closet is centrally located with respect to DHW uses to minimize delay to hot water and associated ‘stranded water’ heat loss and waste.
Only waste pipes are in the slab, all DHW piping is above the slab, the open web truss floor system used to facilitate routing of plumbing, electricity, and ventilation services.
First floor bath/laundry has a clothes washer and a drying closet – a space with louvered doors in which wet laundry is hung to dry. This space is ventilated by an HRV exhaust register. This minimizes energy use in drying clothes, saves the cost of a conventional clothes dryer, a problematic envelope penetration and the resulting thermal bridge of a clothes dryer vent, and dries clothes more gently.
As you can see, a lot of thought goes into all facets of the design including energy systems, mechanicals, and client goals and lifestyles. If you’re interested in learning to use the Passive House Planning Package and in designing your own Passive House, be sure to check out my BuildingEnergy Masters Series course, Passive House Design. It starts September 22nd, and I hope you’ll be a part of it.
NESEA advances sustainability practices in the built environment by cultivating a cross-disciplinary community where practitioners are encouraged to share, collaborate and learn.