The government is sitting on hundreds of pages of evidence and scores of submissions about housing affordability it is unable to use because it let its inquiry into the subject lapse.

News of the quashed inquiry emerged as Treasurer Scott Morrison delivered a speech in which he declared housing affordability to be an "important policy focus" of the Turnbull government in the new parliamentary term.

The inquiry was initiated by Morrison's predecessor, Joe Hockey, in April last year. Undertaken by the House of Representatives economics committee and chaired by Liberal backbencher John Alexander, it took evidence from the Treasury, the Reserve Bank, ANZ Bank, the Law Society and housing economists.

Mr Alexander said at the time it painted a picture of a nation turning from a "commonwealth", with huge home ownership, into a "kingdom" made up of landlords and serfs. One of the ideas considered by the committee was a winding back of negative gearing.