RE5004 Chap.2 Housing Demand, Supply and Submarkets
Housing Demand, Supply and Submarkets
Shocks meet different slopes
Housing demand responds to income, household formation, credit, user costs and expectations. New supply depends on land, inputs, technology, regulation and time.
A common demand increase therefore produces a larger price response where supply is constrained and a larger quantity response where building can expand.
Market boundaries matter
Property type, tenure, neighbourhood, vintage and quality separate housing into submarkets.
Filtering links structure ageing and maintenance cost to household sorting, while reinvestment or accessibility change can reverse the path.
Hold the initiating shock constant
A controlled comparison begins with the same rightward demand shift in two places and changes only supply responsiveness. Steep short-run supply sends more adjustment into price because the existing stock cannot appear instantly.
Flatter long-run supply permits construction, conversion or redevelopment to absorb more demand.
Geography, planning, infrastructure and input capacity explain why the curve differs; they are not extra demand shocks to add casually.
Follow durable stock through time
Housing quality can decline as structures age, but filtering adds a sorting process: units move through market tiers as maintenance costs and willingness to pay change.
Renovation, neighbourhood investment or improved access can interrupt or reverse that path. A strong submarket answer identifies the relevant households and stock, states the horizon, traces price and quantity, and then asks whether movement between segments changes the initial boundary.
What this chapter covers
- 01
Tenure choice and permanent income
- 02
Housing as derived demand
- 03
Demand and supply shifters
- 04
Short-run and long-run elasticity
- 05
Housing submarkets
- 06
Filtering and gentrification
Worked example · free
Comparing two supply responses
- 2Hold the demand shock fixed.
- 2Compare supply elasticities.
- 2State price and quantity incidence.
Key terms
- Derived Demand
- Demand arising from the services and access another good supports.
- Supply Elasticity
- The responsiveness of quantity supplied to price.
- Submarket
- A bounded segment with its own demand, supply and clearing price.
- Filtering
- Movement of durable housing through quality tiers as structures age and households sort.
- Permanent Income
- Long-run expected income relevant to durable tenure commitments.
Housing Demand, Supply and Submarkets FAQ
Why can equal demand growth create different price changes?
Supply conditions divide the response between price and quantity. Constrained land or approvals make the curve steep, while developable land and responsive construction allow more units to absorb the shock. The comparison requires the demand shift and horizon to stay fixed; otherwise different income or credit changes could explain the outcome.
In the short run, even an expandable city may respond mainly through price because projects have not yet completed.
Why is short-run supply usually less elastic?
Planning, finance and construction take time, so the existing stock cannot adjust quickly. Long-run supply can respond through new building and conversion, subject to geography and regulation. Durability also means most available units were produced under earlier market conditions.
The relevant elasticity is therefore tied to a period and place, not a permanent label attached to a city regardless of infrastructure or policy change.
What makes filtering different from depreciation?
Depreciation describes quality loss. Filtering adds household sorting through a quality hierarchy as maintenance costs and willingness to pay interact, and reinvestment can reverse that movement. A building may physically deteriorate without moving to a lower market tier if its location improves, while a sound building can lose position when accessibility or neighbourhood demand weakens.
Keep physical condition and relative submarket status analytically separate.
How do you choose the boundary of a housing submarket?
Start with the households, property attributes and locations that plausibly share a clearing process, then test whether prices and responses differ across tenure, type, quality, vintage or neighbourhood. A useful boundary is narrow enough to preserve the mechanism but broad enough to contain meaningful transactions. If a shock produces opposite responses inside the segment, refine the boundary before interpreting an average.
Assessment move
For each scenario, write the submarket, initiating shifter and time horizon before giving directions. Practise controlled comparisons where the demand shock stays fixed and only supply elasticity changes. Draw the short-run stock as difficult to change, then annotate which long-run channel—construction, conversion or redevelopment—could respond.
Build a two-column shock ledger: income, household formation, credit, user cost and expectations on the demand side; land, inputs, technology, regulation and delivery time on the supply side. Never place the same fact on both sides without explaining two distinct mechanisms. For filtering cases, add a quality ladder and track the building, household group and maintenance decision separately.
Ask what evidence would distinguish depreciation from neighbourhood revaluation or reinvestment. In timed work, end every diagram with a sentence comparing price incidence and quantity incidence, then state the market boundary used. If the answer says one city is simply more expensive, revise it until the slope, horizon and adjustment channel explain why.
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