Damp walls in garage??

[Bar]

We recently bought a house and got a garage build in back garden. Its 25 sq. m, not attached to house and has one back door, one window and the garage door. I have noticed the walls are becoming damp with rain but seems to take very long to dry out internally and externally. It is not insulated or plastered inside as its only being used as car garage. However, I have recently been told tools and other equipment will rust. It looks to always be damp towards the floor and rising up. Not a lot of money at the moment, was wondering does anyone have any cheap solutions to this problem?

 

[Sconhome]

Is the garage rendered externally with a sand : cement mix with waterproofer?
Was a damp proof course built into the blockwork?

It may be that the render is inadequate or non existant and would need to be done correctly to solve your problem. If you have no DPC you would need to get this injected. Neither are cheap solutions, you could expect to pay in the region of €1k for either (room either side of this budget should be reckoned for)