How Do You Sell a Green Apartment Building Today?

It's all about health, resilience, air quality, and safety.

Walkway looking on to court
The exterior corridor on an apartment building in Vienna, Austria.

David Schreyer

A real estate investor in Kentucky contacted me recently to pick my brain about what would be the best ideas for a "green" building in today's world. What attributes might make it be worth more money or fill up more quickly compared to a typical building? This is not a simple question because those things that might excite me, such as being high efficiency or low carbon, are not drivers in the marketplace. People usually won't spend a nickel on it and don't really want to think about it as they drive their SUV into the garage. As American writer Upton Sinclair wrote a century ago, "It is difficult to get a man to understand something, when his salary depends on his not understanding it."

I have also noted before that there is a reason the Well Building Standard is eating everybody else's lunch and why actor Gwyneth Paltrow is a multimillionaire: They are all about health and wellness. Passive House started as a standard that dealt with energy, which nobody cares about, including me—carbon is the problem now. However, I recommended that my investor look closely at Passive House for a number of reasons.

1) Air quality: In most apartment buildings, occupants have pressurized corridor systems where "fresh" air comes in under the apartment door from the corridor. I always thought this was a terrible system, with the air almost filtered through dirty carpeting, and all that dust, poop, and pollen getting pushed in. Post-pandemic, it's a disgusting idea. Most buildings designed to the Passive House standard have individual air-handling systems in the unit and are sealed off from the corridors.

2) Airtightness: As we learned in California and Australia during wildfires, houses and buildings designed to the Passive House standard have much lower levels of particulates inside, thanks to the lack of leaks and the continuously filtered fresh air. I wrote: "It may well be time to make Passive House level airtightness requirements part of the building code; these forest fires will not be the last."

Hours of safety
Building performance in a simulated power outage.

Rocky Mountain Institute

3) Resilience: We noted after the Texas freeze that our homes should be thermal batteries that can keep the heat in (or out) if the power and the gas go out. As the 2020 study by the Rocky Mountain Institute demonstrated, a typical 1950s home would take eight hours to drop below 40 degrees in a power failure, while a code-compliant home would take 45 hours, and a Passive House would take 152 hours. (A net-zero ready home, a standard touted instead of Passive House, only lasted 61 hours).

4) Noise and Comfort: As we have noted when discussing mean radiant temperature (MRT), our level of comfort comes from a combination of air temperature and MRT—together forming the operative temperature. If your body is losing heat to cold walls with low MRT, you will feel cold and uncomfortable. We have also noted that buildings built to the Passive House standard are much, much quieter; testing on a Passive House wall showed a 10-decibel reduction in noise transfer, a 50% reduction.

5) Fitwel: I also recommended that my investor look at Fitwel certification, where buildings are designed to encourage healthy living. I wrote earlier about it: "Inside, accessible, attractive and safe stairs are a must. And of course, it must be tobacco, asbestos, and lead-free with good air quality and acoustics. Apartments must have 'at least one window with views of greenery.' And of course, there has to be an exercise room and fitness equipment available free of charge."

balcony hole in front of window

David Schreyer

6) Look at exterior corridors: We previously discussed the problematic air quality in buildings with pressurized corridors. Frankly, in these times I don't think anyone is happy sharing elevators and narrow corridors with other people. A recent tragic fire in New York City demonstrated what happens if fire doors are not properly closed: Smoke travels fast.

Floor plan
Floor plan 2 through 4.


I wonder if it wouldn't be a big marketing plus to have single loaded exterior corridors, as is often found in Europe and used to be common in Florida. You step out your front door and you are outside, not in a corridor. Suites have windows front and back, providing light and cross-ventilation. I have seen so many plans recently of apartments with "dens" and home offices with no windows, which I have no doubt are often being used as bedrooms. With single-loaded buildings, it should be possible to avoid this completely. This project in Vienna, Austria even had light wells and rails so that people couldn't get right up to the window and peep in.

Cykelhusit Oboy
Cykelhuset OhBoy in Malmö, Sweden.

Lloyd Alter

Cykelhuset OhBoy in Malmö, Sweden had wide, generous exterior walkways and special brackets where you could lock your bike right outside your door, though many residents just rolled their bikes inside.

There are other ideas that I forgot to mention to the investor, including getting rid of gas for a healthier interior. As Carbon Switch founder Michael Thomas learned, people care a lot more about their health than cutting carbon or saving energy. I would also say, keep it low—say, under six stories—so that people will use the stairs more often.

intelligent City section

Intelligent City

And, consider mass timber. John Klein and his Generate Architecture team are doing great things with it, and Oliver Lang is doing exterior corridor designs with it in his Intelligent City project.

20 Niagara Street
20 Niagara Steet in Toronto, Canada.

Lloyd Alter

I have not built an apartment building for 20 years. When I last did it, I tried to be innovative with exterior walkways (on the rear) and through units with cross-ventilation. I lost a fortune and my company, which is why I am a writer now. And the building type has not been replicated. Perhaps I shouldn't be handing out advice, but I believe I have learned a bit in the years since, and I know what I would do now. It will be interesting to see if anything comes of this.