Water condensation in concrete garage with metallic roof

I'm having a condensation issue with our "mid-60s built" garage made of precast concrete walls and metallic roof

When outside air temperature drops below 10°c the walls are literally "sweating" and the roof "showering" everything stored underneath

(the 2 last pictures are taken in a hotter day so it is dry inside). Worth also noting that there is an air gap between the roof and the walls, running on each side of the garage and at the rear

From what I've read online the most efficient way to fix this condensation issue might be by improving the insulation, I have a limited budget and DIY skills so I'm looking at something not too pricey and fairly easy to do.

For now I was considering to glue some aliminium bubble insulation foil similar to this one :https://www.amazon.co.uk/SuperFOIL-Garage-Door-Insulation-6sqm/dp/B01ENLVTBA  or some polystyrene insulation boards. (Right now I'm more lining toward the aluminium foil as I'm worried about the durability of the polystyrene).

Am I going in the right direction  ? ?

I would be really interested to have your thoughts about it ?

Edited September 29, 20215 yr by M_Phlip