# Forum Home Renovation Roofing  Leak where verandah roof joins the house

## berries

My house and verandah have separate corrugated iron roofs. The verandah was added later, and the sheets extend a short distance below the sheets of the roof. The overlap between these two levels is not sealed. The house roof is quite a steep pitch, while the verandah roof is reasonably flat. In the north queensland wet season, water travels up the verandah roof and leaks under the house roof iron onto the verandah below. We have a lot of trees overhanding our roof, and because of the flat pitch of the verandah roof, they sometimes come to rest just below the join, allowing water to bank up there and making the problem worse.  
I would like to seal the join between these two layers and stop this happening, but the fix is made more complicated by the fact that the curves of the corrugated iron on the house and verandah levels are not perfectly aligned, so the shape of the space between the two roofs varies, making the weatherproof foam and rubber inserts that are usually suitable for this purpose, unsuitable.  
I have considered using some kind of weatherproof tape but due to the misaligned corrugations, I am not sure that I would be able to make the tape curve as necessary and make a good seal. I have also considered some kind of waterproofing membrane treatment but I don't know much about them. Does anyone have any suggestions?

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## r3nov8or

Solid flashing made to a profile like that attached may be possible, depending on the  clearance and access to the underside of your main roof to install it. Presumably there is at least a small gap along the entire length.  
The one I've drawn has two creases. You could probably do it with one crease. The second crease will add strength and ease of handling. 
Slide it under and only fix it to the verandah roof at the top of the corrugated ridges (not the valleys)

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## berries

Thank you for your suggestion. I fear that the water would still flow up the corrugation valleys and run under the flashing? I know it seems strange for water to flow up the pitch of the roof, but it is a very low pitch and we get _very_ heavy rain! There are not even any gutters to slow the water getting away, but it still seems not to drain away quickly enough in heavy rain, especially if there are any leaves sitting on the verandah roof, although I get up there very frequently and sweep them off to help the water get away as efficiently as possible. The overlap of the original roof and the verandah roof is sufficient to stop water entering if the rain is reasonably light. This is why I suspect I may have to somehow actually seal the gap between the sheets?

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## r3nov8or

Sounds like the verandah roof has not been made in line with regulations. Corrugated needs at least 5* fall. Trimdek 2*, Lokdek 1*, but whatever roofing is used it is most important is to install the correct back wash prevention when building. 
Using my original suggestion, you would then have one flat surface to use those standard foam profiles under the front edge of the verandah flashing to stop the water washing back under the flashing. 
If the sheets are so close (overlapping) so as to not allow the flashing, then gallons of silcone sealant may do it as a cheap solution.  
Your wet season will always come, so rebuilding the verandah properly will give you the best peace of mind.

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## berries

The pitch actually is 8 degrees...the suggestion to use flashing and then seal the gap with the foam inserts is a great one! Thanks muchly!

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## r3nov8or

You said it was flat!!    8* isn't 'flat'.  :Smilie:      Down here we hear about the wet season rains but it sounds like it's about time I witnessed it it  :Smilie:      good luck with the roof.

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## manchild

Thats exactly how we fix this situation.Make sure that the flashing is at least 300 mm on each side and dont put the screws too close to the bottom or the middle on the top roof.DONT use any sealent or foam or whatever it WILL rust your sheets under the overlap by trapping moisture  .It meant to be a dry join.Measure the picth first and make sure when you are order the flashing it has a 10 mm lip on the bottom ,it will stop it from kicking up or warp.

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## rusel

Flashing is the way to go.
If you have access to the underside of the veranda you can bend up the ends of the valley of the veranda sheets. By doing this the water has to get over the bent up bit before it leaks 
Russell

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## berries

Will do! Thanks

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