starlored

I have but I was trying to find an easier/cheaper option.

That was my thoughts, I'm currently in the process putting new insulation in the loft space and the foil bubble wrap on the rafters. (Plenty of airspace) It's going to be a Ball ache to redo the walls as there's a toilet cistern and cupboards on the "outerwall"

I have a single brick utility that's been battened and then plasterboarded. The problem is there's no insulation in the void between the brick and plasterboard. The easiest way to remedy this would be to pour eps beads in, would this cause damp issues or would sealing the brickwork outside eliminate this.