How do I fix this roof problem?

[aussiblue]

Anyone got a solution to this?  My 1982 Dalfield built home (double brick concrete tiled) has had a problem with the valley gutter leaking into the eves and onto the soffits since new. I had the builder come back and attend to it under the warranty when teh first rains came  but it has never been totally fixed and has got leakier by the year.

 A few weeks ago I replaced the lower rusted portion of the galvanised valley gutter/flashing and found the cause. The support rafters that runs the length of the valley from the peak of teh roof down to the perimeter gutters the side valley gutter support boards actually finish at the bottom end about 15cm or more below the gutter and facia. The fix the builder employed it seems was to loosely put a couple of offcuts battens about 10 cm long near the perimeter gutter to raise the extreme end of the valley gutter and raise the tiles along the edge of valley all the way up the roof with bits of broken tile. However this has meant that about 3 meters of the valley gutter between the makeshift offcut supports and the higher supported part of the valley gutter is unsupported with its slope is too shallow and the weight of the adjacent concrete tiles are flattening the valley gutter so it is no longer  V shaped. I only recently replaced all my perimeter gutters with aluminium gutters so I don't want to drop the facia (steel) and perimeter gutters if it can be avoided; and I don't thing that would be praticable anyway. I am wondering if I can simply lay and nail new support battens/boards the full length of the valley gutter so they essentilay raise teh existing supports so they then finish above the perimeter gutter and the tiles along the edge no longer require additional support? Am I likely to run into any new problems doing this? Are there better economical solutions? Note that apparently we use different profile valley gutters and related roofing support construction in WA and SA (e.g. see http://www.stratco.com.au/products/b...valley-gutter/).

My concern is that I suspect the support rafter and support boards are in the right place at the roof peak and drop away as they descend and that I may really need very long wedge shaped battens to address the issue. But perhaps I could  just step down the batten thickness one centermeter or so at a time as I go up the roof a metre length at a time perhaps?

Note that I have replaced the valley gutter with the currently available slightly wider valley guttering hoping this would help minimise the risk of leaks and some years ago I replaced the broken tiles bits that were raising the tiles (without realising why they were there) with square profile adhesive bituminised square profile strips from Bunnings .

The pictures beloe are taken facing the lower end of the valley gutter and lifting the last tile on the right hand side. The galvanised metal to the left is the steel metal facia. You can see the offcut up against that; the offcut was put on its edge but falls flat once the valley gutter (shiny brown metal) and tile are put back. I can't see that these offcuts were ever going to solve the issue. The offcut is sitting on the right side (looking from the lower end) valley support. You can see the gap between the valley gutter of the top of the facia is about twice the thickness of the offcut/valley support board.

And yes I need to do my annual clean to get the crap out of the top of the gutter guard.

I have also replaced the other two valley gutters in my house and they sit higher and support the valley gutter all the way to the facia/perimeter gutter. I actually don't think I can drop the perimeter gutter to fix this as the soffits sit in a slot in the metal facia on one side and on top of the outer layer of the double brick cavity wall on the other.

[Kermit]

Wow. That looks like it might be beyond the scope of a forum, but I hope you get some ideas. I take it you have had advice from plumbers? Other builders? 

[Craig]

Go speak to a roofing specialist. Patch jobs will just leave the problem there to constantly come back.

[pursya · Accepted solution]

If you believe that the problem can be repaired without professional intervention then I would measure the gap that you wish to achieve and insert a steel section in place of the timber offcuts.
Use an adhesive like T-Rex http://soudal.com.au/trexpowerbond/ to fix the steel in place. The adhesive can also be used to build up any areas on the valley that you think may be leaking water. (as you believe the valley is being flattened by the tiles) T-Rex can be used under water so even if it's damp in there it will adhere, just make sure surfaces are clean.
Good luck.

[aussiblue]

That idea has potential and I have more skill and experience in working with metal rather than timber so it appeals to me. I think could even just screw some lengths of galvanised angle steel in place to act as supports from the point where the valley gutter first start to departs from the support board to above the perimeter gutter.

[aussiblue]

No; it is not fixed unfortunately. Having a good look again today and test fitting the steel option I have come to the conclusion that come spring (when the rain has gone) I am going to have to pull up all the existing valley support boards the full length of the valley and install new ones of the correct pitch. Essentially it looks like the original roofer constructed the roof on the assumption that the eves and perimeter gutter would finish a few inches from the outer layer of bricks and the valley rafters and supports were pitched accordingly. The tiles on one side of the valley at the lower end also sit above the existing valley gutter so it is almost as if one side of the roof was build with correct pitch. The proximity of the front door and power supply fuse box to the end of the valley gutter also means I need a more secure fix; I don't want water leaking into the fuse box or the door lintel. Of course putting in new valleys supports will have to take into account that the rafter underneath also has the wrong pitch and I will have to install wooden spacing blocks of varying thickness between the rafter and new valley support boards. Not a five minute job.

[Jason]

Hi @aussiblue,

Have you made any progress with your roof problem? 

I hope all is well and you're not in an area that has suffered from heavy rain in the past week. 

Jason

[aussiblue]

No; it's been too wet to get on the roof.  It's been OK since I replaced the valley gutter as long as I keep the immediate perimeter gutter very clean. However, I am sure as the weight of the tiles slowly does its work on the unsported lower end I will have issues again.  I have seen some similar houses where the valley gutter appear to vanish into the eaves at the internal edge of the soffits and feeds a downpipe  where the valley gutter meets the cavity wall so perhaps that was what was intended (although the meter box and front door location would I think make that a little impratical).  Others where they have a spill drain onto the roof at the point where valley gutter becomes unsupported.  My daily walks with the dog has become a neighbourhood roof examination exploration.