Roof valley and eaves construction

[DaveyN]

Hi guys, looking for guidance on curerent practise for constructing the eaves detail and valleys as my house is currently being reroofed and I need to make sure its going to be watertight.

The pitch is 43deg, rosemary tiles, breethable membrane and counter battens over membrane onto rafters. Membrane onto felt support trays. The problem seems to be that the joiner may have the facia boards to high, he says needed for kick on tiles but what is happening is that the counter battens are not going low enough so the first tile batten is having to be fixed directly to the support tray so defeating the object of letting water out. What is correct way to set this out.

Secondly the joiner has fitted floor boarding material for the lead valleys direct to the rafters but has laid the membrane underneath. I also cannot now see how battens can be fixed for the tiles other than nailing tiles to the floorboard material. What is normal practise with this.

Any help appreciated from roofing community.

 

[noseall]

the valley boards are usually fixed between the rafters - sitting flush with the rafter top.

these boards should be wide enough to accommodate the lead or grp valley and have enough extra width to catch the roofing battens (lathes). also, there should be two battens running up each side of the valley to deal with the valley sides.

the fascia should be tall enough to provide a kick for the first course of tiles.

with plain tiles the eaves lathe will be rather close to the fascia. it does get quite cluttered at the eaves detail. we tend to use a strip of 12" dpm instead of eaves trays.

i have seen roofers fix the eaves first, then membrane on top, then the full courses of plain tiles.

why the counter batten? insulated rafters??

 

[DaveyN]

Hi, thanks for the reply, its a warm roof (between and under rafter insullation) construction and the architect has detailed the counter battens on the approved plans as he did the felt support tray. The counter battens nailed over the membrane on the rafters have been cut to the sides of the valley support boards only. No other battens have been fitted and the lead hasnt been turned up at the edges etc. hope that makes sense.