Using secret gutter with deep profile tiles

[garyo]

Are there any circumstances where a secret gutter (abutment) is a bad idea? I have a fairly standard ~45 degree roof and I'm planning the roof detail on a small dormer that we're adding.

The tiles are Marley anglias (!!) Do I need to be careful in terms of not ending up with the secret gutter in line with the hump in the tile which might make it difficult to discharge the gutter back on top of the lead apron, or will it be workable regardless?

Thanks

 

[^woody^]

You should be flashing over the tiles

 

[Leofric]

Is there a secret gutter detail for Anglia tiles in the technical details section of the Marley roof tiles website I haven't looked but that should explain it.

 

[datarebal]

flash over the tiles, anglias have a deep profile .. secret gutters block

 

[bobasd]

as above. typically, its best to use a one piece cover flashing for profiled tiles, and soakers and stepped cover flashing for flat tiles and slates.
in most cases, secret gutters are a roofing death wish.

fwiw: roofers set the roof out so that they control where the tiles will end up, and not just willy nilly lay tile hoping for the best.
even difficult courses of tile can be shunted and nudged to avoid any secet gutters or similar.

 

[Leofric]

for what it's worth

 

[garyo]

Thanks chaps. We have an existing dormer that's done with lead flashing, and I don't find it particularly attractive, but then I don't find wet ceilings attractive either.

The new dormer will be clad differently to the existing dormer (deeper with ventilation etc), so if I can land the tiles well then I should have scope to make the flashing less prominent.

 

[^woody^]

so if I can land the tiles well then I should have scope to make the flashing less prominent.

Less prominent on a roof up in the air?

Anyway you don't want to be back to square one with wet ceilings after you have formed a gutter with profile tiles.

 

[garyo]

Less prominent on a roof up in the air?

It's a chalet bungalow, so unfortunately the roofing detail is easily within eyeline as you stand on the driveway. I may be being unfair - I don't think the existing flashings have ever seen any patternation oil so don't do themselves any favours.