Kg house per kg person – material need per function

At the end of the summer season, some thoughts that came up while practicing ‘doing nothing’ on camping. And I had to think of an always nice comparison with cars: the weight of the car versus the weight of the person to be transported. In other words, how many kg of car per kg of person. That has only grown over the years. I remember when I was young we drove a 2CV (Citroen) or R4 (Renault), that 2CV weighed 615 kg empty. And with a R4 I went on holiday as far, as I do today (all Europe) . On long stretches I already drove 1 ltr. in 20 km.! It’s a shame that this is still not standard 40 years later.

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Which, of course, that also depends on the weight. Take today a SUV, which weighs almost 2 tons, plus another 80 kg for the driver. That is 25 to 1! (by weight) With the R4 it was 8 to 1 or thereabout. That too is actually ridiculous. That is, in physics, shooting a mosquito with a cannon. And indeed, the fuel consumption, if possible only went up, instead of down.

Incidentally, there are still some smaller and lighter cars available, but not as light as then. Currently, popular smaller cars such as the Peugeot 206 already weigh almost 1000 kg, and the Citroen C1 / Peugeot 108 / Toyota Aygo are slightly below that: 815 kg. To be honest, when I looked it up, that even didn’t seem too bad. The biggest difference is of course not that a lighter car is no longer available, but that the majority now drive much heavier cars.

And then there are the electric cars… a car from 800 kg then quickly becomes 1200 kg or more. 50% more weight (and material impact) to transport the same person.

In addition to the car itself, there is also the infrastructure over which those ungainly monsters must be able to move. And faster. Not even in maximum speed but in average speed. As a result, roads are constantly being adapted and widened. A simple highway easily weighs 1000 kg per m2, and as I calculated before, the Netherlands has approximately 57 m2 of road per person… [1] For every Dutch person there is just as much indoor space as paved outdoor space in m2! But then also about 57000 kg in weight and material per person for roads…. (slightly less, local roads are simpler)1

bicycles

Then of course there is the bicycle. Widely acclaimed as the most effective means of transport. No wonder, the weight is only 1/10 or thereabouts of the person to be transported. And the driving energy also has to be generated by the person himself. The downside is that it goes slower. It is always a trade-off between time (speed) and space.

That is of course rapidly changing at the moment: the bicycles are becoming electric, and are a lot heavier, and the battery is added as well. These bicycles go towards 25 kilograms, and a battery of another approximately 3 kg.

Then the ratio becomes 1 to 3 or around. Still on the good side, but it’s getting less…! Plus the operational energy is introduced again, something extra needs to be added. But if that results in a doubling of the speed (and doubling of distances covered, and therefore a decrease in the 25:1 means of transport, that is pure profit. )

houses

But then, isn’t that the same story with houses? You never hear about it, but why should we look at houses and buildings differently?

An average house in the Netherlands weighs about 1000 kg per m2, and the average living space per person in the Netherlands is 65 m2. So 65 tons have been invested to keep 1 person of say 80 kg., 0.08 tons, dry and warm. A ratio of more than 800 to 1, or 800 kilograms is invested per kilogram of human being. That seems a bit exaggerated, doesn’t it? And it even can’t move …

Ok, the materials of a house are usually much less energy-intensive than those of a car, and also less subject to exhaustion, but in 2021 that still seems very obsolete. In the first place, of course, this can be reduced by living in a smaller house. Then the housing shortage is immediately solved as well. (for example: a residential base of 30 m2 pp, and to be taxed above that… [2])

Another way is to build biobased, in timber frame construction for example, then halving the weight per m2 is feasible, with the same performance, around 500 kg/m2. With 30 m2 of biobased shelter you arrive at 15 tons pp, or 187.5 kg per kg body weight. That already makes a significant difference, not only in weight, but also in impact, including embodied energy. Not to mention the CO2 benefits of biobased materials. Which are fixed forever, yes? ( over the nonsense of calculating the lifespan of buildings – why wouldn’t they last forever? – I will write another time!) Incidentally, the majority of people worldwide still live in small, simple and biobased or mud houses, and some even live in tents or slums, with shelters from simple sheet material from the landfill [3] ( they live ‘circular’, we would say here…). There are even cultures where they still live underground, in excavated dwellings called troglodytes. The Romans even made underground villas! In Tunisia, many are still inhabited: these are homes that dont cost material, but yield material, the excavated soil, negative weight, as it were…!

To put things in perspective: All homes in the Netherlands together weigh approximately 1100 megatons. All people together in the whole world weigh about 600 megatons. So less than all our homes in the Netherlands.

What is remarkable in this regard: If we all start living smaller and biobased, that will make a huge difference in the kg load of housing. But that doesn’t change anything regarding the infrastructure, the roads that connect everything! While those , as we saw before , have at least an equal burden per person . To reduce that too, the weight and maximum speed of the cars would have to be reduced, say back to the R4s and 2CV’s, and especially to narrower roads, and even semi-paved roads. Maybe even halving roads, creating one-way streets at neighborhood level! { as proposed in our research at the time into Kerkrade West [4].

I was thinking about all this, sitting at the campsite in front of my old VW camper van. It weighs less than 2 tons, all included, and we live there with 2 people. Or 1 ton pp. ‘The 1 tonne pp society’ is even feasible…[5]. Then we have shelter, and we are mobile, both with the van itself and with the bicycles on the back. So, why don’t we go ‘on vacation’ forever? With working from home nowadays, that should work…?

Anyway, you get strange thoughts, just sitting on a campsite.

 

 

[1] on roads and sidewalks:

http://ronaldrovers.nl/exploring-sidewalks-impact-similar-to-housing/

http://www.ronaldrovers.com/the-end-of-the-road/

http://www.ronaldrovers.com/a-circular-road/

[2] http://www.ronaldrovers.com/m2-living-per-capita-in-europe-and-consequences/

[3] http://www.ronaldrovers.com/from-zeb-to-zeeb-0-embodied-energy-buildings/

[4] Existing district of tomorrow, Kerkrade West, reports : http://www.maxergy.org/urban-scale/

[5] http://ronaldrovers.nl/van-energietransitie-via-materiaaltransitie-naar-een-welvaartstransitie/

1 Hardened road surface for a two lane 80 km road is 7,5 meter. With a total length of roads of 135000 km, divided by 17,5 million inhabitants gives 57 m2 pp , excl side walks etc.

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