As the rainy season approaches, I'd like to try and stop our garage getting wet. It appears that there's a leak of some sort (there's always a wet patch after heavy rain) and looking this morning after last night's rain it seems that the cement/asbestos sheeting for the roof is actually damp underneath - I guess it must be porous.
Is it meant to be porous? Its been there many years by the looks of it (though we've only been here 4 months). Is there anything I can paint on it (bearing in mind its not exactly a clean roof!) to stop it passing water through it?
The amount of water though that has come through (small long puddle under one of the metal supports) makes me wonder if its actually being blown under the capping, running down the underside of the sheets and then dropping off the metal supports where it touches the sheets.
Any suggestions? Its annoying having everything getting wet when it rains (well, boxes end up sitting in water, acting like sponges and then get smelly - I've lifted some up off the ground - but its a pain to have to do lots of them).
Thanks
D