Thanks for your response, but why ? My understanding is that the sag in underfelt and gap between mortar and valley upstand is to allow any moisture on underlay or tile backs to escape. How does this get out of solid bed ?
Hi, new to this - I'm replacing concrete interlocking tiles on a gable running back to valley. The gable is flush with adjacent house wall hence has no eaves to speak of. This results in valley mortar meeting verge mortar at a point at the bottom whereas the rest of roof has normal eaves with a...