31 March 2017

Techs and the city

In lots of regions around the world, the city of the future will be dense and vertical. The city of Houston, Texas, is the opposite of this vision. Like several of the big cities in the US, Houston is a widely spread city. It will take time for the Texan city to transform, if it ever transforms. There, the American Dream is still to own a big house and a big car. And spending two hours a day in the big car does not seem to be a major concern for the Texans.


However “if a house has to be built, I want it to be a very high quality house which will last for decades,” Scott says. Scott Frankel is the Co-President of Frankel Building Group, a design and build construction company founded by his father. The company is the leading green home builder in Houston.

One Climate One Challenge Meza Gheung Houston engineered insulation technologies city dense vertical durable sustainable energy consumption (1 (1)
Every year the US National Association of Home Builders gives away a BIG award, a Best In Green Young Professional of the Year. It recognizes the work of a young professional who make the building industry more green and sustainable. Scott won the award last year in 2016. We had the chance to meet him in his office, in western Houston. The office is full of the awards the construction company won in the past.

Scott explains: “To me, green first means durable. This is what the company thinks: it is wrong to build a house which will fall into ruin after only 15 years. It is wrong for the environment and it is wrong for the image of the company! And you know, the weather here is tropical; it can be very hot and very humid during summer. The constructions are having a hard time! They face extreme conditions, the degradation is fast.

There are hundreds of different materials which you can use to build. One needs to choose those materials correctly and the construction can last much longer, and save energy every day. This is what we do. We are continuously surveilling technological innovation. We are constantly learning. I regularly spend time in class!” Scott adds: “Furthermore we want to limit as much as possible our impact during construction, through environmentally-friendly methods. Also our construction mistake indicator is low; we almost never redo.”


“Since 2009, we have worked closely with our suppliers to choose the right elements and raise the quality,” Scott says. “An example is our insulation technologies. Firstly, efficient insulation will protect the structure and the inside of the house from humidity, preventing degradation. It also makes the inside air healthiest. Secondly, good insulation saves lots of energy!” Scoot took us to one of his houses under construction. He showed us the insulation technology which was used, the Zip System sheathing. The layered sheathing is composed of engineered wood on the outside and foam on the inside. The wood comes from local sustainable forestry. “The system goes with a 30-year warranty,” Scott says. Durable! Globally speaking, wood is a very good option for the structure of not-so-large buildings. Wood is biodegradable, it has good longevity and it insulates better than concrete.

One Climate One Challenge Meza Gheung Houston engineered insulation technologies city dense vertical durable sustainable energy consumption (1 (1)
The Zip System, by Huber. ©Huber

Heating or cooling a building can represent up to 60% of its energy consumption. Efficient insulation can dramatically reduce this consumption. In France for instance, estimations say 20 million homes are not well insulated. These last years, the country has put into place incentives in order to accelerate thermal renovation works. It is expected that these renovation works of old buildings and houses can divide by 4 the energy consumption related to heating. This is probably the France's biggest challenge in regards to their transition to a low-carbon society.

Glass (or glass wool) insulation material is a sustainable natural material. In particular it can be made from recycled glass. It is thermally efficient and it can be chemical free. Brands are for instance: EcoBatt, Foamglas and Isover. In Paris, the recently built Louis Vuitton Foundation is insulated with Foamglas technology. ©EcoBatt/Foamglas

“Another example is the high quality windows and doors which we install,” Scott adds. “Our double-paned windows are filled with argon gas, which improves insulation. They are very resistant and mechanically robust: we won’t need to change them before a very long time!” The Manager concludes: “We continuously have around 40 houses under construction. Thanks to large volumes, we manage to offer houses with similar prices than our competitors, but with higher quality and durability. We industrialize, we standardize.” The existing technologies may not be environmentally perfect but they show the path to sustainable construction.

One Climate One Challenge Meza Gheung Houston engineered insulation technologies city dense vertical durable sustainable energy consumption (1 (1)
Despite the humid local weather, the structure of the house we visited is made of wood. Wood is an environmentally friendly material. Excellent insulation ensures its protection.

Why will the city of the future be denser and more vertical? Because it will mean less greenhouse gases emissions. More vertical city means residential buildings instead of individual houses. Some researchers even declare that the city of the future must be made only of massive skyscrapers. A truly vertical city. The key purpose is to get the homes, the offices, the schools, the shops closer together. Dense and vertical cities reduce transportation distances, thus emissions. People can walk more, or use their bike. The concept of Central Business District (CBD) should disappear: a large city should have several business districts. People can live closer to their workplace.

A concept of vertical city, in Singapore, by WOHA. ©WOHA

In addition a dense and vertical city reduces the need for roads and decrease air pollution. It gives space to parks and preserves arable land around the city; food can be more local. It also makes the inhabitants of a district feel part of a community. This is complicated sometimes in a spread out city like Houston. A dense city facilitates sharing economy. And lots of studies show that sharing economy must grow in the future in order to reduce greenhouse gas emissions from industry. We can share cars, bikes, washing machines or electric drills. We do not necessarily need to own one. There is one Earth only; we must learn to share.

©Vertical City

Taking off from Houston!


17 March 2017

Hawaii in search of resilience

Hawaii Sea Level Rise Resilience Adaptation Flood Sydney One Climate One Challenge Meza GheungResilience. It looks like the title of a science-fiction movie! It could be one day. For sure it is today a term which is used more and more when talking about the city of the future. What does resilience mean? In biology, the resilience is the capability of an ecosystem or specie to confront a shock and to return to normal after it. As for cities, the definition is quite the same; the shocks being social, economic or… climatic. 


“Beaches are a great public resource here,” Samuel says. Samuel Lemmo is the Administrator of the Hawaiian Office of Conservation and Coastal Lands. “One of my key missions deals with coastal ecosystems, communities, and all issues related to our coastlines. Lots of people live in coastal areas in Hawaii. Erosion is already a massive problem. We also experience large-scale flooding in the low‐lying areas of the State. Climate changes and sea level rise are one of our main concerns.”

Hawaii Sea Level Rise Resilience Adaptation Flood Sydney One Climate One Challenge Meza Gheung
Samuel’s Office is part of the State Department of Land and Natural Resources.
“In 2014, when by law a Hawaii Climate Adaptation Initiative was launched, it was decided that the lead agency would be my office,” Samuel explains. “Quickly I suggested starting a major job: prepare and release a report about sea level rise and Hawaii. We must make our home more resilient! Hawaii is the only island State of the US. Since the beginning of 20th century, the sea level (SLR) has risen by more than 17cm. The report is a vulnerability and adaptation report. It aims at preparing us for future SLR and presenting recommendations to reduce our exposure to the hazards like erosion and flooding.

The Report will include the economic impact on structures, properties or natural resources. Displacing of the communities or relocation of roads will also be assessed. We want to use case studies to better explain the scenarios; we want the recommendations to be presented creatively and tactfully so that people do read them and understand them.”


“Around ten people work on the preparation of the special report, not only from Conservation and Coastal Lands Office but also from the University of Hawaii School of Ocean Earth and Technology,” Samuel says. “Our local research aims to enhancing our assessments of how Hawaii will be impacted in regards to SLR. Our models should be a nice scientific contribution! Indeed they go further than what is usually performed. Traditionally modeling sea level rise has consisted only in projecting to the land the elevation of the sea. We go further. We add three additional parameters: erosion of the coast, passive inundation and annual high wave flooding. In regards to erosion, for instance, we input soil maps and geological data to model erosion effects.” Water spreads differently in contact with sand, volcanic porous rock or hard rock.

On the right, an illustration of passive inundation. Water can come from the ground! Especially if the ground is porous. Florida experiences the phenomenon, they call it sunny day flooding. ©Office of Conservation and Coastal Lands

“We have coral reefs here. They serve as a physical barrier. Well, if the level goes up, energy of the waves will not be stopped anymore, which means we will receive more powerful waves. They will go further landward.” Globally speaking, concerning changes in water-masses and air-masses, it is very complex for scientists to imagine all the induced consequences. Samuel concludes: “With the information, decision makers will be able to better prepare and better response. The report should be available end of this year.”


When we were in Sydney, Australia, we had the chance to meet with Kristin Gabriel who is the Manager of the Resilient Sydney project, for the City of Sydney. She could explain us that “Sydney joined the 100 Resilient Cities initiative in 2015.” The initiative, started by the Rockefeller Foundation, helps cities around the world becoming more resilient. “We identify two categories of disruption. First, chronic stresses refer to constant issues. It can be social cohesion or housing prices for instance. In Sydney, public transportation is an example of permanent concern. Some people are geographically disconnected from the city center because public transportation is not satisfactory there. This deficiency also affects the social cohesion and equality.

Hawaii Sea Level Rise Resilience Adaptation Flood Sydney One Climate One Challenge Meza Gheung
Kristin and Carolina.
Secondly we distinguish the acute shocks which refer to sudden events that threaten a city such as fires, floods or disease outbreaks. In the case of Sydney, extreme heat waves are the number one cause of deaths. Also we consider other climate extremes like storms and floods.” Sydney and Honolulu, Hawaii, are member cities in the 100 Resilient Cities network. We visited or will visit several others during our 2016/2017 trip: Singapore, Melbourne, Wellington, Christchurch and New York City.

A pumping station of Miami Beach. ©City of Miami Beach, Greg Allen/NP

During the last decade, Florida had to deal with more and more floods and storms. Miami has started to adapt: the city builds higher streets, advanced drainage systems and water pumping stations. The city solutions inspire others, not only in order to face SLR, but also to face heavy rainfalls which will be more frequent in lots of regions around the world. In New York City, the Dryline, or BIG U, project consists in constructing a high-water barrier, protecting Manhattan from the rising waters. Year after year, the Big Apple experiences both stronger hurricanes and stronger snow storms. As we said in our previous article, in few decades the climate will have changed. In lots of cities around the world, the adaptation transformation has begun.

Hawaii Sea Level Rise Resilience Adaptation Flood Sydney One Climate One Challenge Meza Gheung
An elevated house, in Houston, Texas.
A nice chart presenting adaptation technologies for coastal areas, according to the Asian Development Bank. ©Asian Development Bank, 2014
Hawaii Sea Level Rise Resilience Adaptation Flood Sydney One Climate One Challenge Meza Gheung
Getting prepared for our meeting with Kristin, at City of Sydney Town Hall!