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A Passive House

By March 4, 2022May 16th, 2022No Comments
Ariel photo of Glenroy Community Hub

The Hub is Passive House certified.

The Passive House design approach empowers us to build better.

Passive House’s are healthy, comfortable, and quiet buildings, full of clean, filtered fresh air.

They are also durable and resilient buildings.

The need to use energy for heating and cooling is greatly reduced (by as much as 90%). The reduction in energy use also reduces the carbon emissions of the building.

Passive House design tools and methods make energy reductions both cost-effective and predictable. You know what to expect with a certified Passive House.


A Passive House building’s airtight layer is like a windbreaker, stopping air from penetrating to the inside.

Creating an  unbroken air barrier is central to Passive House performance and durability. In design, we do the “red pencil test” to check that an air barrier line can be drawn around each cross-section of the building without the pencil ever leaving the paper. In the field, this air barrier is built through a combination of sheet membranes, fluid-applied membranes, tapes, and sealants that transition without interruption between components of the building envelope.

Airtightness is verified with a blower door test, a key measure of performance and construction quality.


A continuous layer of insulation wraps Passive House buildings, keeping them warm in the winter and cool in the summer. Passive House designers also harness this insulative layer to prevent condensation inside the building.

Fresh Air with Heat Recovery

The delivery of filtered fresh air with heat recovery helps make Passive House buildings havens of clean air and energy efficiency.

HRVs (heat recovery ventilators) and ERVs (energy recovery ventilators) are “balanced ventilation” components that supply a continuous stream of fresh air to living spaces while simultaneously extracting stale air, odors, and indoor pollutants from kitchens and bathrooms.

Inside these devices, a heat exchanger—a honeycomb of straws that creates a very large surface area between air streams—allows heat energy in the outgoing air to passively transfer to and warm the incoming air without the two airstreams ever mixing. In the summertime, the opposite happens, with cool outgoing air cooling the incoming air. Filters in the unit remove pollen and pollutants, with pre-filters available to protect indoor air from intense outdoor pollution events.

No thermal bridges

A thermal bridge is any building element that allows heat or cool to bypass a building’s thermal barrier. It’s like a hidden thief of thermal energy, undermining performance and durability.

For example: a concrete floor that continues from inside to outside; a poor window frame; or a steel beam that penetrates an exterior wall. We eliminate thermal bridges by introducing thermal breaks into those assemblies—gaps or insulative elements that stop the flow of thermal energy through an assembly.

High Performance Windows and Doors

With each window and door opening we make in a Passive House building, we are essentially punching a hole through a wall and its airtight, weather-resistant, and insulative layers.

So, having high-performing (such as double-glazed) windows and doors and how well we tie them into the surrounding wall, is critical to maintaining the performance of a Passive House building.


Good shading is important to avoid too much heat getting into and staying in the building during summer. Deciduous trees are great for this, with their bare branches in winter and shade-providing leaves in summer. Architectural elements like overhangs can also play a role. So too, can window shades and screens, especially ones located at the exterior of the building.

More information

For more information on Passive House go to: