What flashing is required for joining these two Colorbond roofs?

[Andythommo97]

Hi guys,

Just wanting some advice around a poorly done patio extension prior to us buying. I'm wanting to repair, and it seems like whoever did this hasn't installed flashing between the original roof and extension causing some water to seep back in. I'm wondering what flashing would suit best. (The second roof has a very low pitch, which im also investigating). 

Thanks. 

[Jason]

Welcome to the Bunnings Workshop community @Andythommo97. We're pleased to have you join us.  

Apologies for the slow reply. Let me tag one of our resident Bunnings D.I.Y. experts in @EricL to assist you, as well as some other helpful members such as @JacobZ95, @tom_builds and @TedBear.

Thanks,

Jason

[EricL]

Hello @Andythommo97 

My apologies for the late reply. Can you please tell us how far apart the corrugated roofing is? Can you also please post a photo of the gap from up top if possible. It might be possible to use a product such as Consolidated Alloys 100mm x 10m Weatherproof Byute Flash Flashing Tape. 

This will allow you to cover the gap of the roofing on the condition that they are not too far apart. It is possible to get a wider flashing tape, but it becomes untenable if the gap is too large. The tape will begin to sag under its own weight so it's best to have the gap very small.

Inserting galvanized angled flashing is also an option, but you'll need to know the angle of the slanted roof. It becomes an issue if the flashing is at the wrong angle as it will begin to gather water instead of letting it flow away.

If you have any other questions we can help with, please let us know.

Eric

[JacobZ95]

Hey @Andythommo97,

Unfortunately, I don't think there is an easy fix to this one. I've had a look through Lysaght's flashing guide (Flashing Guide) and the best example I can find is the below image.

 

This style of flashing is called an "apron flashing". They are produced by Lysaght and can be ordered through the special orders desk at your local Bunnings. 

This would likely require you to remove a row of screws from the upper pitch of the roof in order to slip the flashing underneath before fixing into place. You will note that the bottom edge of the flashing has been trimmed to sit flush with the profile of the lower roof pitch. This can be achieved by using a combination of Left, Right and Straight tin snips. You would then need to silicone the bottom edge using something like Selleys 300g Cottage Green Roof and Gutter Silicone Waterproof Sealant to prevent water flowing back underneath the lower edge of the flashing.

Hope this helps,

Jacob