Housing/footprint

From the change wiki

How many resources does it take for people to have housing?

This is a page for some estimates.

Single-detached home

Note: This is the footprint of only the construction of the house. (...)( will later include heating, electricity, and maintenance renovations )


Labor

We could estimate labor by looking at some costs:

  • labor costs, obviously
  • material costs, because these generally reflect the labor that goes into producing the materials

We don't want to count other costs:

  • zoning permits and other bureaucracy - maybe these exist in our current society but they don't have to exist fundamentally - there are probably much more efficient & fair ways to make decisions about housing (or at least, the process could do without bullshit jobs) - so we leave this out.
  • land value - this depends on the location and it isn't a reflection of labor requirements. Also we will calculate land in another section anyway. So here we leave this out too.

Housing costs have gone up recently, but this is more a function of demand rather than any inherent increase in the amount of labor needed to build a house.


Quick estimate: How many labor hours go into a house:

house.typical_price_before_covid
400000 $
typical_wages_before_covid
18 $/hour
Average wage of workers in construction, materials production, and other relevant trades
what_fraction_of_costs_reflect_labor
70%
The percentage of costs that fit into the categories we care about (mentioned above)

house.typical_price_before_covid * what_fraction_of_costs_reflect_labor / typical_wages_before_covid hours house.rq_labor (calculation loading)

How about labor over time:

family.size
4 people
house.lifespan
80 years

house.rq_labor / house.lifespan / family.size hours/week per capita (calculation loading)

Shockingly low. Did I get something wrong?



Land

For one, there's the land that the house sits on: Quick estimate:

house.size
2600 square(feet)

house.lot_size (calculation loading)

But also the land that it takes to grow the wood for the house:

board_foot
(1/12) ft^3
Weird unit but ok.
house.wood_volume
16380 board_foot
Amount of wood in a typical house
wood.density
0.8 g/cm^3
For converting between wood mass and wood volume
tree_farm.productivity
10 tons/hectare/year
Wood yield of a typical "tree farm" forest
Agroforestry Carbon Sequestrationhttps://www.sustainably.run/co2-verification
tree plantations of pine and eucalyptus can sequester an average of 10 tons of carbon per hectare per year.

If we assume that half of this carbon is in the tree wood (the other half being in leaves and roots), and if we assume that 50% of the mass of wood is carbon atoms, then: This means 10 tons of wood per hectare per year.

house.wood_volume * wood.density / house.lifespan / tree_farm.productivity (calculation loading)

If you have some idea how to estimate the land footprint of other materials, please start the discussion. For now, let's hopefully assume it's small enough to ignore.



General

The following calculations are based on US home energy stats that don't distinguish between the type of dwelling but distinguish between the type of energy use:

usa.population
336997624
Using stat from 2021
usa.home_electricity
1519 billion kilowatt hours / year
Electricity used in all USA homes
How is electricity used in U.S. homes?
https://www.eia.gov/tools/faqs/faq.php?id=96&t=3
Stats from 2021.

"Total consumption"
usa.misc_residential_electricity
901 billion kilowatt hours / year
Electricity not used for heating nor cooling
How is electricity used in U.S. homes?
https://www.eia.gov/tools/faqs/faq.php?id=96&t=3
Stats from 2021.

"Total consumption" minus "space cooling", "space heating", and "water heating".
usa.home_air_cooling_electricity
235 billion kilowatt hours / year
Electricity used for cooling the air in homes (i.e. air conditioning)
How is electricity used in U.S. homes?
https://www.eia.gov/tools/faqs/faq.php?id=96&t=3
Stats from 2021.

"space cooling"
usa.home_air_heating_electricity
207 billion kilowatt hours / year
Electricity used for heating the air in homes
How is electricity used in U.S. homes?
https://www.eia.gov/tools/faqs/faq.php?id=96&t=3
Stats from 2021.

"space heating"
usa.home_water_heating_electricity
176 billion kilowatt hours / year
Electricity used for making hot water (in pipes) in homes
How is electricity used in U.S. homes?
https://www.eia.gov/tools/faqs/faq.php?id=96&t=3
Stats from 2021.

"water heating"

usa.misc_residential_electricity / usa.population watts per capita (calculation loading) The USA is known to be an energy-hungry country with a big carbon footprint. But when looking at only home electricity use, not including for heating and cooling, the energy demand is actually quite modest.