Gap between concrete and garage wall

[TDJ]

I've removed a crumbling strip of concrete approx 40mm wide between a slab and the garage wall, as I thought sealing this would stop the garage getting damp. Under the 1cm of concrete is empty space and soil. Would refilling with concrete be likely to stop damp ingress or would filling with sand/gravel help more by aiding drainage? Do I just accept my garage will always be damp?

 

[JohnD]

digging a trench below the level of the slab, and filling it with cobbles, flints or pebbles would allow water to drain through and soak away. The advantage of clean middle-sized stones is that they have good air gaps between them and do not encourage damp to rise by capillarity, as earth or sand will.