Bad Weather Proved It: New Housing Helps All Renters, German Study Shows
"A 1% increase in housing supply cuts rents by 0.19% — and the benefits reach far beyond luxury apartments
A new study in the Journal of Political Economy Macroeconomics ("The Impact of New Housing Supply on the Distribution of Rents" by Andreas Mense) shows how building new housing affects rental prices. The study uses weather-related construction delays in Germany as a natural experiment.
Why it matters: The study provides the first causal evidence that building market-rate housing helps reduce rents even for lower-income residents, challenging the notion that new construction only benefits wealthy renters.
The big picture: Mense found that when construction gets delayed by weather, it creates measurable impacts on housing supply and rents. This allowed him to trace how new housing triggers a cascade of moves that frees up units across different price points.
By the numbers:
- A 1% increase in new housing supply reduces average rents by 0.19% 
- Each new housing unit triggers about 4 moves within the rental market 
- Only 5.2% of rental units are new construction, while 94.8% are "second-hand" 
- 94.8% of moves are by renters 
- The effects translate to a short-run demand price elasticity of -0.025 
- New supply primarily affects single-family housing construction 
Key findings:
- Rent reductions occur across all quality levels of housing 
- Effects are equally strong in high-demand markets with strong employment and income growth 
- Single-family home construction helps reduce rents by freeing up rental units 
- The impact is relatively uniform across unit types and local markets 
- Lower-quality units see effects of -0.13 while higher-quality units see up to -0.28 
How it works: The research identified several key mechanisms:
- Renters often "jump up" the housing ladder when new units become available 
- Their vacated units become available to others, creating a beneficial chain reaction 
- This "second-hand supply" effect integrates different market segments 
- Moving costs play a key role by discouraging small, incremental moves 
- The effect spreads quickly across the entire local rental market 
Methodology details:
- The study used German data from 2010-2017 
- Examined how weather-related construction delays affected housing supply and rents 
- Built economic model analyzing household housing choices 
- Used panel data from the German Socio-Economic Panel 
- Analyzed impact on 94 planning regions over 8 years 
- Controlled for employment, unemployment, and student population 
The market dynamics:
- 49% of new unsubsidized units go to renters becoming homeowners 
- 32% become rental units 
- 19% are bought by existing homeowners 
- Moving chains reached low-income areas 60-70% of the time 
Policy implications:
- Market-rate housing construction can effectively improve housing affordability 
- Supply-side interventions are effective policy tools 
- Restrictions on market-rate housing supply can harm low-income renters 
- Results hold even in markets experiencing strong demand growth 
The bottom line: Building new housing, even at market rates, can be an effective tool for improving housing affordability across income levels. The study suggests policymakers should focus on removing barriers to new housing construction and creating tax incentives for optimal land use.
What's next: Future research should examine how other housing policies interact with these market dynamics, particularly studying:
- Forward-looking nature of housing choices 
- Peculiarities of housing as a second-hand market 
- Distributional consequences of various policies 

