When house prices are expected to rise, the representative house mover
has an incentive to secure his purchase price (i.e. exchange contract
s) on the 'new' house before exchanging contracts on the sale price on
his 'old' house. If all house-movers adopt this stance, the imbalance
between buyers and sellers causes a self-fulfilling speculative price
bubble. Transactions costs do not represent a barrier to such specula
tion in the house market, as such costs can be considered as being sun
k costs for first-time buyers and owner-occupiers intending to move fo
r non-speculative reasons. This idea is formalised and empirical evide
nce is presented which suggests that speculation is a significant dete
rminant of house prices in the United Kingdom. (C) 1997 Elsevier Scien
ce B.V.