“The living tapestry of a mixed community”: the words of Aneurin Bevan in describing his post-war ambitions for council house building. Britain did pretty well back then at building council homes, and subsequently under minister of housing and then prime minister, Harold Macmillan.

We can learn from our past without romanticising it. That is what our cross-party Shelter Housing Commission, launched this week, seeks to do. It is a direct challenge to all parties to commit to transforming our country’s approach to social housing.

The facts of the failure of the housing policy over the last generation make uncomfortable reading. In the decades after World War II through to 1980, both Conservative and Labour governments built an average of 126,000 social homes each and every year. Last year, there were just 6,000 new homes for social rent delivered and the record of the last Labour government on building social homes wasn’t much better.

What is important about our report is that after a year of analysis, consultation and discussion with thousands of people, we conclude that unless we reach again for the ambitions of that post-war era, we will never solve the housing crisis our country faces.

A 30-year low in homeownership, out of reach prices and a swollen insecure private rented sector are the visible symptoms of our worsening housing crisis. We argue that the catastrophic failure to build enough social homes is a key cause. Social housebuilding has plummeted, and the private sector cannot pick up the slack.

That is why our report says we cannot go on as we are as a country. We need a once in a generation change in approach. We call for the building of 3.1 million social homes over the next 20 years, seven times more than in the last 20.

We want a return to the vision of Bevan and Macmillan, which sees social housing not just as a broken safety net for those who have nowhere else to go, but also as a springboard for people to meet their needs and aspirations. For those who are now in dire need and risk ending up on the streets; for struggling young families who could save for their future if they lived in social housing; for the hundreds of thousands of elderly people stuck in insecure, costly private renting.

But to make this happen, we need a change in philosophy. Instead of “the market will provide” – the dominant approach of the last generation across both major parties – we believe social housing must again be seen as a key plank of investment by government in the country’s future.

We make no bones about the price tag that comes with this plan. The £10.7bn of extra annual investment we are calling for is significant, but this cost is in the context of a government capital budget of over £60bn. Furthermore, the net costs to government of the investment we are calling for will be significantly lower, once benefit savings and higher tax revenues are taken into account.

For the sake of our country, we cannot afford not to make this investment. If we do not do this, we will shell out even more money in housing benefit and the housing crisis will get even worse. The risks are clear: homelessness getting even worse, half of young people unable to buy, and up to one-third of older people forced to live in insecure, high-cost private rentals.

At a time when we seem more divided than ever, the truth is that the housing crisis touches everyone. We know there is overwhelming support for the need to build more social homes, across political and Brexit divides.

The moral, social and economic case is unanswerable. Now we need the political will. We are determined this will not be a report that gathers dust on the shelf. Today Shelter and its supporters begin the campaign to make this report a reality.

We owe it to people across the country – young, old, Northern, Southern – to make this happen. By learning the lessons of our past, we can build a better future which answers the enormous challenges of the moment.

Ed Miliband MP is MP for Doncaster North and former leader of the Labour Party.