I have an old house with old roof beams etc, is it still possible to install insulation?

I have an old house with old roof beams etc, is it still possible to install insulation?

80-90% of homes built before 2000 have no wall insulation, which means that 15-25% of your conditioned air is escaping via your walls. To insulate walls in an old house you can use blow in insulation.

Most ceilings can be insulated with layers so existing insulation can be added to with batts of dense material such as polyester, sheep’s wool, and fibreglass wool (with or without reflective foil to reflect the sun’s heat.)

If your home has no easily accessible attic space (i.e. cathedral ceilings), you can still insulate it with polystyrene boards.