Housebuilding slowed in the final three months of 2018 and was flat for the whole of the year, despite Theresa May’s promise to make a personal mission to oversee an increase in housebuilding.

Figures released by the housing ministry showed building work began on 40,580 homes in England during the final quarter of 2018 – 8% down on the previous three months.

However, the figure is significantly up on the 2015 figure. In the final three months of that year, just under 30,000 homes were started on construction sites in England.

During the whole of 2018, work began on 165,160 new-builds, which was almost exactly the same as the 2017 total. Only the number of completed homes rose in the past calendar year, up 1% to 165,090. Kit Malthouse, the housing minister, said he was delighted with the result.

In November 2017, May reiterated a previous pledge to fix the broken housing market. “For decades we simply have not been building enough homes, nor have we been building them quickly enough ... my government will be going further to ensure that we build more homes, more quickly,” she said at the time.

Despite various initiatives, housebuilding is yet to occur at the rate demanded. In January, a cross-party commission, led by the housing charity Shelter, urged ministers to embark on a government-backed housebuilding programme to construct 3.1m new social homes in the UK over the next two decades.

Shelter has said 280,000 people in the UK are homeless. Previous government figures showed that affordable homes – for sale or to rent – make up a relatively small, but growing, part of the housing supply in England.

In the six months to 30 September 2018, there were 9,909 new affordable homes under construction, up from 6,989 in the same period of 2017.

In his spring statement this month, Philip Hammond announced a £3bn scheme to fund 30,000 affordable homes. The chancellor said the government was on track to reach its target of building 300,000 new homes a year in Britain.