Pretty much, it costs around £200k to build a regular 2-3 bed house, plus the land plus fees.
So you won't get one for less than £300k anywhere.
Furthermore, each time a new piece of legislation comes in to improve the environmental or safety credentials of construction, whilst positive, there is a cost attached to that. Also worth a mention that inflation effects houses as well and that runs at 3% ish per year. House prices have pretty much tracked the rate of inflation for the past 20 years.
Final point is that the average age of a tradesman is going up all the time. The average age on construction sites is over 45. Their salaries will increase above the rate of inflation, which is great that traditional working class roles are paid so well. It does mean that house price inflation will continue.
TLDR. They won't stop going up and ithe majority is not due to greedy developers.