Veronica, the landlady in our first rental had split the house in two and was living in the lower half. Bless her, she was just as cold and damp as the rest of us upstairs. She had recently emigrated from South Africa and bought a "home and income" to make ends meet. We too lived in Africa many years ago and always had brick houses there so it must have been a shock for her.
As far as I'm aware there are no government grants here to insulate and damp-proof houses. So retro-fitting can be quite expensive. You also have to live somewhere whilst it's being done.
Remember a lot of these houses were built when electricity and fuel was really cheap. Fuel prices have increased markedly in recent years and shows no sign of getting any better. We had a similar situation in the UK before the oil crisis, no one had insulation or cared about the conservation of energy. Government grants and building regulations have improved things greatly since then.
There is a movement towards building masonary houses here. Insulated slabs are being laid, new houses have insulation in walls and roof spaces, they are being built on reinforced concrete slabs and roofing felt can now be found under the roof tiles (keeps out dirt and sand). If you want you can have double glazing and central heating too. You can even get heat pumps to warm your house in winter and the pool in summer!