The Potential of the Mobility Transition (MT) for tackling the housing crisis is: 

up to 107,371 flats in Berlin alone.

My PhD research shows that the land for 107,371 flats could be provided in Berlin alone if the MT were implemented, providing homes for over 193,000 people. 

Where and how could these flats be built?

While research to date has focused on the on-street land consumption of motorised individual transport (MIT), off-street automobile infrastructure (OSAI; such as petrol stations, car dealerships and car parks) has not yet been considered systematically. My GIS analysis shows that OSAI occupies 22.2 km² of valuable land in Berlin. This is significant when you consider that this exceeds the total area of the Friedrichshain-Kreuzberg district (20.4 km²), which has a population of around 290,000. Parking infrastructure outside of the street alone covers over 18 km² in Berlin. (See Chapter 2)

The transition towards a sustainable mobility system requires a shift in modes of transport and a reduction in motorisation rates.
 In my case study of Berlin: MIT -61.4% (Hirschl 2021, based on the EWG law, which demands carbon neutrality in Berlin by 2045), and a reduction in motorisation by 51.9% (UBA). (See Chapter 4) 

Based on this modal shift and shrinking motorisation rate, land currently occupied by OSAI through e.g. car dealerships and car parks would become obsolete and could be reused for housing and other public purposes, such as green and blue infrastructure. 

The high potential of parking infrastructure
By using urban planning parameters such as the actual density in Berlin at bloc level and the reduced land consumption through OSAI, I calculated that e.g up to 74,430 flats could be built on land which is currently used by off-street parking. (see Chapters 3 and 4)

Best Practices
Examples from Berlin demonstrate how OSAI has already been repurposed. For instance, the site of a former car dealership now accommodates around 500 people as well as a kindergarten. (See Chapter 5)

Consequences
The sooner the MT is implemented, the sooner the potential for housing can be realised. However, this potential can only be unlocked through holistic collaborations between politicians, urban planners, mobility planners and civil society. In Chapter 6, I present five areas of policy recommendations that could support this process.

The PhD thesis is freely accessible here:
https://doi.org/10.24355/dbbs.084-202510131116-0 

(to download click the action button at the bottom right of the thesis)