One of the most hotly debated topics of the recent party conference season was housing.  Is the Help to Buy Scheme a valuable spur to the market, or the beginning of a house price bubble? How close are we to winning the argument for lifting the HRA borrowing cap?

Is the rhetoric of dramatically increasing supply matched by a credible set of policy means?

This is a debate that matters an awful lot in London.  London has failed to build enough homes for the best part of 30 years.  This is not just ‘affordable' homes.

It is across all price points and all tenures – homes to rent and to buy.  With London's population continuing to grow, we need to build more than half a million new homes by 2021 just to keep pace with the annual increase in households.

To meet the unmet need, a further 283,000 will need to be built.  And these figures are at the lower end of the scale of estimates of London's housing need. Londoners are now experiencing the highest levels of overcrowding and pay the highest rents in the UK.

More than 41,000 London homeless households are in temporary accommodation.

This is not just affecting people's lives and health and their children's educational attainment.  It will increasingly impact upon London's future economic growth.

The CBI has recently cited housing as one of the capital's most significant weaknesses and a potential contributor to a loss of business to London.

London Councils believe we should be focusing on three major themes: cash, consent and capacity.  We need to leverage sufficient cash to fund construction at a wholly different level than we have previously.

Lifting the HRA cap is important here, but so could be freeing up housing association equity, increased institutional investment in the private rented sector and shifting from personal subsidy to bricks and mortar.

On consent, there are more than 124,000 units with permission in London that have not been built.  Councils are not the major impediment here, but the overall system does need to be more agile.

Finally, on capacity, among other things we need are deferred payments on public sector land and working to fully exploit the potential of small builders to add to the critical contribution of large developers.

We are going to need to identify, debate and test as many good ideas as we can if we are serious about tackling this issue.

John O'Brien is chief executive of London Councils