just nearly completed a hell of a job 140sqm of indian sandstone , when it rains there is a puddle which i am hoping i can just lift some slabs up and rebed them a bit higher rather than chopping 5 inches of mortar out
i had a feeling it was an air lock somewhere as the downpipes had a dripping hiss sound, which i guess cannot be made unless their is a gap i.e air somewhere in the pipe.