A thought experiment compares the carbon impact of three new single family homes with the same block if it contained a duplex, a triplex, and a fourplex.

If it were legal everywhere, Michael Anderson writes, gentle density would confer massive carbon savings and ease the transition away from fossil fuels.
To illustrate, Anderson poses a thought experiment where three large new homes are constructed on one block, while a duplex, triplex, and fourplex are built on a site of the same size. "If we compare these two blocks after all the new homes are complete, the housing-related carbon emissions per household of the Plex Block will be about 20 percent lower," he writes.
It makes sense that smaller living spaces cost less carbon (and dollars) to heat in the winter and cool in the summer. And in the case of the McMansion, most of that space isn't even lived in.
Anderson also notes that when "missing middle" housing is permitted, the positive environmental effects extend to transportation. "This density effect is probably strongest if it's creating new options for living in a transit-rich, walkable area specifically for people who want to live a low-car life but couldn't previously afford that sort of neighborhood."
FULL STORY: A DUPLEX, A TRIPLEX AND A FOURPLEX CAN CUT A BLOCK’S CARBON IMPACT 20%

Trump Administration Could Effectively End Housing Voucher Program
Federal officials are eyeing major cuts to the Section 8 program that helps millions of low-income households pay rent.

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Canada vs. Kamala: Whose Liberal Housing Platform Comes Out on Top?
As Canada votes for a new Prime Minister, what can America learn from the leading liberal candidate of its neighbor to the north?

Washington State’s Parking Reform Law Could Unlock ‘Countless’ Acres for New Housing
A law that limits how much parking cities can require for residential amd commercial developments could lead to a construction boom.

Wildlife Rebounds After the Eaton Fire
Following the devastation of the Eaton Fire, the return of wildlife and the regrowth of native plants are offering powerful signs of resilience and renewal.

LA to Replace Inglewood Light Rail Project With Bus Shuttles
LA Metro says the change is in response to community engagement and that the new design will be ready before the 2028 Olympic Games.
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