Condensation proofing the bedroom should I replace with better insulation? Damp can be a major issue in the home. Find answers to questions or post your own here.

[adiwood]

I used a dehumidifier over winter which helped greatly with the insulation issues but I'm now looking at ways I can make the bedroom more insulated before next winter.

I've made a small hole to see what's behind.
The room has an 8 ft long window above stripped wood cladding and some water proof sheeting on the outside and plasterboard backed with 1cm of polystyrene on the inside. There is a ventilation gap in between.

Should I look to remove the old plasterboard and replace with something that has a much deeper insulation material? Maybe 25mm or 50mm polystyrene or should I add an additional layer?

[welsh brickie]

I would remove the plasterboard and install triso super 10 insulation, it will make a dramatic difference and its only 35mm thick