Cavity wall insulation

[Foreveramber]

When my house was built I had the kingspan cavity wall insulation boards put in. Now twenty years on I'm advised to pump insulation beads into the cavity wall to fill any gaps between the brickwork and the kingspan insulation in order to insulate the house more. I'm wary of this as someone mentioned it could cause damp. My house is near the coast and sits on a height. Please advise.

 

[Micks'r]

Don't pump your walls until you know how and where you are losing your heat.

Most houses in Ireland suffer more heat loss through convection losses (aka draughts) rather than conduction losses (which insulation may address if done properly). Adding extra insulation to address a convective loss mechanism is a waste of money and in your case probably risky too (from moisture ingress pov).