Garage conversion/ ventilation

[Douja]

Hello,

I hope you guys can help me.

My garage is a pitched garage and I recently started using it as workshop and storage.

I have installed loft boards during the summer and started storing items at the top loft.
I had installed plasterboards ceiling (without insulation) and walls with insulations DIY (Polystyrene)z
However; all my items in the loft are getting mould.

So my question here, would insulating the top ceiling and the walls at the top help with the mould? Or it wouldn’t make a different.

Or redoing the whole ground floor of the garage with better insulation is a better option? What’s the right way to do it to avoid mould and condensation building up in the loft.
Thank you

 

[Jameshow]

Is there a damp proof membrane in place?

Damp maybe getting into the garage.
Have you ventilation in the apex of the roof ridge line or an air rock high up.

You could put an extractor fan in place.

 

[Douja]

Is there a damp proof membrane in place?

Damp maybe getting into the garage.
Have you ventilation in the apex of the roof ridge line or an air rock high up.

You could put an extractor fan in place.

I don’t think there’s any damp proof membrane in place. When We DIY the walls in the summer, we only put the polystyrene and the plasterboards on the walls. That’s it. Then followed by loft boards installed by someone but no insulation was put in place.
And yeah there is an apex on the roof.