Clash of the manifestos: house building

"Under Labour, house building fell to its lowest peacetime level since the 1920s"—Conservative manifesto

"Britain is in the midst of the biggest housing crisis in a generation, with the lowest levels of house building in peacetime since the 1920s"—Labour manifesto

The two main parties have seized on the very same claim: that we are building fewer houses per year than at any peacetime period since the 1920s.

The only figures readily available going this far back are for England and Wales. They show both claims to be technically accurate; both parties are deploying the same facts against each other.

Fewer houses were built in England and Wales at the end of the Labour government than at any point during peacetime since the 1920s. That situation continued during the coalition government, with house building remaining broadly at this low level.

The "peacetime" caveat is needed, because during the Second World War house building plummeted. Some incarnations of this claim have neglected to mention that, but in the manifestos at least it has been included.
To put these claims in further context, a government consultation document from March this year states that "for decades there have not been enough homes to meet the needs of our growing and ageing population".

So for the Conservatives to say in their version of the claim that house building "fell" to these quite striking low levels under Labour doesn't give the whole story. House building has been broadly falling since the 1960s under governments of all colours—assigning blame for this to one particular government doesn't reflect this wider context.