Lead under valley 1st tile

[kestrel]

Im doing a bit of repair work on tiled valley with redland plain concrete valley tiles,  much the same as this image i found online. The valley is felted under the tiles

 

From what iv read there must be some lead fitted under the first valley /tile and a half to create water run off however im not sure on the exact detail required.

 

My first valley tile sits on top of the two mitered eaves tiles shown in red in the attached diagrams. what im not sure about is the required shape and how far the lead needs to extend past the two mitered eaves tiles.

Also should the lead be folded down to hook around the edges of the eaves tiles so it doesn't slip?

I got the following image online and sketched over it showing the mitered tiles in red and two different interpretations of the shape of the lead(in green) but no idea if either is correct

 

My initial understanding was the lead should cover the eaves tlies and the space behind them and is folded down over the side of each tile before butting to the next eaves tile. Like this

 

 

Or should trim the back of lead to suit the outline of the mitered eaves tiles and only fold the top edges of the lead over the eaves tile and have more overlap at the sides like this?

 

 

already have a 12" roll of lead, will that be wide enough to do the job?

 

Thanks for any advice

Kes

Edited December 13, 2020 by kestrel

[Oz07]

I'd imagine so it covers the joints. Your eaves tiles do this on the straight runs

[joe90]

You’re tiles, like slates rely on double overlap to carry water that gets between tiles/slates as they have no “joint” between them. The bottom row of half tiles should be cut at an angle so they are under the bottom valley tile “joins” but some rely on lead instead/as well.

Edited December 13, 2020 by joe90

[Temp]

If you are making valley soakers can you turn the 12" wide lead sideways to make them as wide as you like or would they be too short top to bottom?

 

 

 

 

[kestrel]

32 minutes ago, joe90 said:

You’re tiles, like slates rely on double overlap to carry water that gets between tiles/slates as they have no “joint” between them. The bottom row of half tiles should be cut at an angle so they are under the bottom valley tile “joins” but some rely on lead instead/as well.

 

so they need cutting to an almost triangular shape like so?

 

[joe90]

8 minutes ago, kestrel said:

 

so they need cutting to an almost triangular shape like so?

 

Yes I would. It also means the other tiles remain flat as it’s a constant level to work from.

[kestrel]

1 hour ago, Temp said:

If you are making valley soakers can you turn the 12" wide lead sideways to make them as wide as you like or would they be too short top to bottom?

 

 

 

 

possibly...tiles are about 8'' top to bottom so might be able to make it out of 12''

 

52 minutes ago, joe90 said:

Yes I would. It also means the other tiles remain flat as it’s a constant level to work from.

thanks