Low-Energy Building Built of Low-Carbon Materials

The Passivhaus or Passive House mantra these days is efficiency first! Meanwhile, the mass timber movement is all about embodied carbon first! Gabriel Ciordas, founder and CEO of visual production platform Creatopy, deals with both in his company's new offices in Oradea, Romania.

He explains: ”I knew I wanted to create an office building made of wood, using cross-laminated timber, that would first and foremost be environmentally friendly; I also had my team’s wellbeing in mind, because I think it’s one of the healthiest offices you can possibly work in.”

The 25,833 square foot building is the largest mass timber building in Eastern Europe.

Reducing upfront carbon emissions appears to have driven the design from the ground up. As the short video—all in Romanian, but you get the idea—shows, instead of your usual foam under the slab, the building is floating in a sea of Energocell foamed glass, made in Hungary from recycled waste.

According to the manufacturer, the powdered glass waste is baked in an electric tunnel furnace:

"The amount of (primary) energy needed for the production of the Energocell® foam glass granules and boards is very low, only about 140 KWh/m³. It is one of the insulation materials with the lowest manufacturing energy requirements. In contrast, the thermal needs of plastic foaming (see polystyrene) or other types of glass foaming exceed 1500 kWh/m³ (a ten-fold of the primary energy needs)."

Treehugger has shown a version of this that is now sold in the United States, called Glavel, which we liked because it could replace foam below grade.

Above grade, the walls are built from 819 prefabricated Austrian CLT panels, delivered on 25 trucks and assembled by ten people in 44 days.

It's not quite Passivhaus

The project is introduced as a "passive building" but apparently didn't quite make the full Passivhaus grade. According to the company blog:

"Creatopy’s office is a certified Low-Energy Building, the second next to Passive House Standard—they are identical in principles. Still, this standard is more permissive to specific values, for cases in which the building’s climate and shape cannot sustain all values of the Passive House Standard."

Ioana Ciobanu of Creatopy tells Treehugger: "There are two factors that have different values (from the ones in the Passive House Standard per se) -in our case, the energy target and degree of air tightness, that due to the climate necessities, are higher than the values envisioned for the Passive House Standard."

I would not have thought that climate was an insurmountable issue, given that there are 23 certified Passivhaus buildings in Romania. The issue is likely the shape, described as "a complex design that integrated perfectly into the hills-dominated landscape while adjusting to our particular needs and specifications."

Architect Mădălina Mihălceanu of Vertical Studio said of the building:

“Our building is developed on three platforms, the level differences being a natural response to the slope of the land which justifies our minimal intervention on the land, a non-invasive approach that helps animate and revitalizes the building both inside and outside.”

It is complicated, resulting in increased surface area. That is why we have mantras like "Sufficiency First" and "Simplicity First," calling for simple forms to minimize surface area and eliminate bumps and jogs which lead to thermal bridges.

The Low Energy Building Standard is part of the Passivhaus building criteria, and allows twice as much heating demand and less airtightness, but is still quite challenging.

However, if Ciordas doesn't exactly practice Passivhaus, he certainly preaches it, recognizing the benefits of reduced energy consumption, reduced emissions, and including the benefit that Treehugger regularly promotes: increased comfort. This is a function of the well-insulated walls. I have noted previously that "the walls and windows are almost the same temperatures as the air they enclose, so you don't gain or lose heat from them very quickly. You are comfortable. And comfortable people are happy and productive people."

Ciobanu makes a similar point in the post: "Altogether, the thermal comfort is high, and the internal temperature is constant. Since the people who benefit from this building have a desk job, the body is susceptible to physical stress factors, impacting performance."

Building to the Passivhaus standard is always challenging. They are really trying to do so much here at once, designing a building with incredibly low embodied carbon through the use of innovative foundations and mass timber, hitting the Low Energy Building Standard, and going all-electric. This is ambitious but necessary. As Ciordas notes:

“In creating this new home for us, we wanted to inspire other businesses to do the same—to choose sustainability over short-term gains because saving our planet has to be a joint effort. Our buildings will outlast us, and the decisions we make in the present will influence the planet we leave to our future generations.”