Why am I studying to be a Certified Passive House Builder?

The catastrophic consequences of unchecked climate change were cemented in my mind by my college classes and followup studies. So, I predicated my decision to build sustainable houses on the urgent need to mitigate climate change. Thermonuclear war or a stray asteroid are the only other threats that are likely to doom humanity. Other than voting for sane representatives, an individual can’t do much about thermonuclear war. One can do virtually nothing about that pesky asteroid. But, each of us can do a lot to limit our contributions to the climate change problem.

Rooftop Solar

I originally thought that Rooftop solar was the solution for an individual to mitigate their home’s contribution to climate change. But, after studying the issue in depth, I am convinced that the more comprehensive passive house strategy is the best solution. I’ll explain.

Cost effective rooftop solar depends on several factors.

1. Does your utility offer net metering? Net metering is when your electric supplier issues credits for the excess electricity that you generate and feed back into the grid. These credits are then used on par to buy the electricity that you need when you’re not generating as much as you use. A properly sized solar system will generate more electricity than you use in the late spring, summer, and early fall, when the days are longer. The accrued credits are then used in the late fall, winter, and early spring, when the days are shorter and you’re not generating as much as you use. Electric providers are pushing to curb the benefits of net metering as I write. Some, like my local utility, don’t even offer net metering. Without net metering, the payback period for rooftop solar is decades, rather that years.
2. For an existing house, does it have a sufficient roof area, oriented close enough to south and without obstruction of the sun’s path to be effective? It it’s a new house, can it be sited with enough unobstructed roof area, facing close enough to south?
3. The raw materials and energy used to produce solar panels and their disposal after their 25+ year life span also raise concerns.

Passive House

This brings us to passive houses. These are houses designed with a comprehensive system including:

1. Super insulation
2. Robust water, air, and vapor barriers
3. Passive solar gain
4. High performance windows and doors
5. Energy recovering air exchangers
6. Alternative energy sources.

A passive house is designed by someone who is trained to look at local climate factors and design a house using the comprehensive system described above. Since passive houses are built to such a tight standard for preventing air, heat, water, and vapor penetration, they always include a heat recovering air exchanger. This provides a steady flow of fresh air to the occupants, without wasting much of the energy used to condition the interior air. Passive house design and construction also prevents condensation that would likely result in mold, mildew, and/or rot.

The energy needs of a passive house from the heating/air conditioning mechanical units (HVAC system), as well as water heating, are greatly reduced. So, the need for alternative energy sources or buying electricity from your utility is lessened. When properly designed and built, a passive house will use 60% less energy than an industry standard house. That’s without counting site produced electricity from renewables. They can take a passive house to net zero energy from outside sources.

Summary

That’s why I’ve chosen to pursue the Certified Passive House Builder designation. I should be certified by the end of July and can’t wait to get crackin’.

Fred Watson

Resilient Builders, LLC