It may not be worth joining the queue for social housing.

Amazing. You wait years for a programme about council housing to be shown on TV, and then two come along at once. Following last month's excellent history of council housing on BBC 4, this week we had Panorama on the acute shortage of social housing and the way that some people with homes cheat by sub-letting them at a hefty profit.

The difficulties facing families looking for a reasonably-sized council or housing association property is not exactly news. However, it clearly demonstrates how Labour failed miserably to ensure that sufficient new council homes were built during the 13 years it was in power.

What was illuminating is how councils such as Portsmouth actively dissuade families and individuals with little chance of getting a home from remaining on the waiting list, so reducing the figures by thousands. If other authorities are doing the same thing (and why wouldn't they?), the estimate of how many people are waiting for social housing may in fact be an underestimate.

The unlawful subletting of council and housing association properties is, of course, a major issue that most social landlords are addressing and probably requires even greater scrutiny. But of greater concern at present is how the shortage of social or affordable housing is going to be tackled when so little government money is being spent on new homes.

Earlier this week, the deadline passed for housing associations to bid for grants from the Homes and Communities Agency to help them fund new homes that will be let at up to 80% of market rents. So-called 'affordable renting' is now the only game in town so far as government-funded house building is concerned. This means people that can only afford cheaper, social, rents will have to make do with existing homes that are re-let, assuming landlords are not tempted to increase rents on these properties as well.

At the same time, some councils have told housing associations they will not support bids to build homes for affordable renting in their area, especially if the people moving into them are offered fixed-term tenancies lasting as little as two years.

It is not an encouraging picture. In some ways, it might seem reasonable that families who can afford higher rents (and only require state-subsidised housing for a few years) pay more and accept a fixed-term tenancy. But there is no indication of where the next generation of social housing is going to come from, or who is going to house the most needy as the supply of existing homes slowly dwindles.

Programmes such as Panorama can help by bringing the issue to public attention, but whether anyone from the coalition government or the Department for Communities and Local Goverment was watching and is willing to take action remains doubtful.