There are 2925 tower blocks in London alone, mainly brought about by population growth exceeding the available land for single or two or three story dwellings. Of these only 18 have sprinkler systems. Upgrading to sprinkler systems, for example, not that that may be a panacea to such buildings ills, would be massively expensive, as is maintaining these structures which were often steel reinforced concrete that proved to be less durable than was envisaged. It begs the question, to me, where do you draw the line as to when population growth is at such a level that free or "affordable" housing, and its safe maintenance is a burden councils are now unable to financially meet?