What moves house prices

It helps to separate two questions that are usually asked as one. What sets the level of prices in a place, and what makes that level move? The answers are not the same, and they operate on different timescales.

What sets the level

The level of prices in a district is, over long periods, a statement about how much people want to live there and how much housing there is. Everything durable feeds into one of those two sides.

On the demand side: the incomes available locally, the number of households wanting to form, the travel time to work and to everything else, the quality and admission arrangements of nearby schools, and the plain amenity of the place, which includes air, noise, green space, safety and how the street looks when you stand in it.

On the supply side: how much has been built, how much can be built, the physical constraints of the site, and the planning regime that governs the rest. Supply responds to price, but slowly and with a lag measured in years, which is why demand changes show up in price long before they show up in new dwellings.

What moves the level

Movement, over months rather than decades, is dominated by money. The cost of credit and its availability set what a given income can borrow, and in a market where most purchases are financed, what can be borrowed is most of what can be paid.

The mechanism is arithmetic rather than sentiment. Hold a household's affordable monthly payment still and change the interest rate: the loan that payment supports changes, and so does the price the household can bid. This is why a change in rates transmits into asking prices with a lag and into agreed prices sooner, and why lending criteria — the income multiple, the stress test, the deposit required — can matter as much as the headline rate.

The supply pipeline

New building affects a district in two ways that pull in different directions. It adds dwellings, which loosens the market. It also changes what the place is: a large scheme can add shops, a station entrance, traffic and construction years, and can re-rank the streets around it. Nearby owners frequently experience both effects at once and attribute the whole result to whichever they noticed first.

Access, and the way it gets capitalised

Anything that reduces the time cost of living somewhere tends to be absorbed into the price of living there. A new transport link, a road improvement, a rezoned catchment: the benefit is real, and it is quickly converted into a housing cost. This is the single most reliable pattern in residential land economics, and it is worth remembering in both directions. Access that is removed is capitalised too.

Value, asking price and agreed price

These three numbers are routinely conflated. The asking price is a marketing position chosen by a seller. The agreed price is the outcome of one negotiation between two particular parties with particular constraints. Value, in the sense a lender or a surveyor uses it, is an estimate of the price a typical willing buyer would pay in normal conditions after proper exposure to the market. A single sale can be far from value in either direction for reasons that have nothing to do with the property: a probate sale under time pressure, a buyer who needs that street for family reasons, a purchase between people who already know each other.

Things that move prices less than people expect

Cosmetic condition moves the speed of a sale more than its price. Extensions rarely return their full cost in a district where the resulting house is now larger than the street supports. And the national narrative — the figure quoted in the news — often has little to do with a particular segment of a particular district, because national figures are averages over places that are moving in different directions.

A short discipline for reading any price claim

Ask what is being measured (asking or agreed), over what period, for which property type, in what geography, and against what base. Most disagreements about whether prices are rising dissolve once those five things are made explicit.