One of the reasons I support building more homes is it will help bring down housing costs if we keep at it. Government research finds a 1% increase in housing stock drives a 2% fall in house prices or rents – remember, housing costs for the average family have doubled from 9% to 17% of income since 1980. But there are other reasons to build. Often we forget how much new building affects the quality of housing, not just the price. The amount of floor space the average private renter has is down 16% since the 90s – equivalent to a city the size of Nottingham. People rent dilapidated and hard-to-heat homes because they have no choice – with too few properties meaning no competition between landlords to up their game. Developers, unsurprisingly, market everything they build as “luxury”, which leads many to say, rightly, that we need more social housing (on which the Welsh government has made more progress than in England since 2010) but others to argue, wrongly, that only the well-off benefit from building. In truth, richer households can always secure a decent home and it’s too often the disadvantaged who lose out on there being too few homes. At the extreme, that includes the high numbers sleeping rough, including in Swansea despite the heroic efforts of local charities and the council. New research from Sweden, using detailed data on people and their homes since 1990, has a wider lesson about who gains from building. Yes, those on higher incomes tend to move into new builds initially, but generally everyone enjoys bigger, better homes. And who is the floor space boost biggest for? Those on the lowest incomes. Building is an agenda for the many, not the few. Torsten Bell is Labour MP for Swansea West and author of Great Britain? How We Get Our Future Back