One can not just continue to sprawl everywhere. We, and other species, need rough ground and countryside and wild places. We for peace of mind, other species for habitats. For sure the short term relief is to build more residential properties but one needs to solve the real problem not simply put off yet again the fateful day when it has to be done. Whether it is prefabs or flats or whatever I don't believe is a big issue. Working out where to put them, is. But the bigger issue is to reduce the population; not go out of our way to grow it whilst using more building as a 'sticking plaster' fix.