My house is double brick, do I need to put in wall insulation? Is it possible to do?

My house is double brick, do I need to put in wall insulation? Is it possible to do?

Double-brick homes have lots of gaps where air can escape, such as decorative vents.

The most effective option for insulating double-brick walls is to use a pump-in loose-fill wall insulation. This product is installed by drilling holes in the wall between the bricks and pumping the insulation into the existing wall cavity. When the work is completed, the holes are filled with mortar.
There are many types of loose-fill insulation on the market, including specially treated (hydrophobic) granulated rock wool and specially treated cellulose fibre, which fill the gap between the brickwork. You can also consider polyurethane foam, which expands after being pumped into the wall cavity or polystyrene beads which prevent moisture transfer.

Check the product's R value: a measure of a material's resistance to heat flow (known as thermal resistance). The higher the R value, the greater the resistance to heat transfer, the greater the insulating effect and the greater the energy (and money) savings.