How to seal gap between gutter and flashing?

[andre999]

Hi all,

I need your advice on the covering the gap between the gutter and the flashing. Today, I have patched it with a tape as temporary measure. I see this as a possibility of water trickle into the flashing and leak to the brick wall that cause water ingress.

To prevent water trickle into the flashing, I have an option which I find it challenging (that don't have a tool to cut) 

- use a galvanised sheet that fits the dimension of length around 44cm and width at least 5cm.

- attach the sheet and seal all the edges with selleys polyurethane

Do you have another solution you can think of?

Thanks.

tape covering the gap

[JacobZ]

Hi @andre999,

Thank you for your question.

Instead of covering the gap, I would leave it open and turn down the end of the flashing.

This can be done by cutting small triangles in the flashing with some aviation snips, so the protruding edge can be bent down, secured with rivets, and then sealed with silicone.

Instead of closing up the gap, this will make any water track down the bent flashing and drip into the gutter.

This is what I assume a professional roofer would do in this situation.

Allow me to tag @Nailbag, @Noyade and @TedBear for their thoughts.

Jacob

[andre999]

Thanks for your reply. The main plan to close the top gap and also close the gutter to the flashing as well. Basically I plan to enclosed the flashing without water coming in whether from top gap or gutter. And drill a hole underneath the enclosed flashing/gutter to allow water to flow out if water exists. 

The unfortunate part of the flashing is the angle is flat. So To prevent water coming thru and into the flashing, I have to enclose the flashing so the water would not reach the wall block which currently showing some water ingress. 

What is your thought on my approach? 

Thanks. 

[JacobZ]

Hi @andre999,

Your approach would also work, but I don't think you need to go to the extent of attaching a new metal piece, as the gap appears to be quite narrow.

Instead, I'd suggest using Byute Flash, which is a high-strength waterproofing tape often used in roofing applications.

This will do the same thing as adding a metal piece without the addition of screws or rivets which can become weaknesses over time.

Just make sure you give the metal a good clean with some isopropyl alcohol or turpentine before sticking the flashing tape in place.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[andre999]

Thank you Jacob for your suggestion. I will use what you have suggested. 

[Nailbag]

Hi @andre999 

Just seconding @JacobZ suggestion to use the flexible Byute tape. Its a very easy and effecting DIY product that will provide the solution your after.

Nailbag

[andre999]

Hi @JacobZ @Nailbag

Did not manage to get the brand you suggested. It is not available in nz. So the bunnings staff introduced a similar product, Masons 40 Below flashing tape. I was abit hesitant to purchase it because it says it is for windows, doors or joinery opening. I hope it works. 

Thanks. 

[MitchellMc]

Hi @andre999,

I'd prefer you use something designed for the purpose, and bitumen-backed flashing tape is the preferred option. The tape you have is more designed for use on window frames to seal vapour barriers before being cladded over. It appears there are a few options in NZ, such as the Bear Flashtac Weather Proofing Foil Tape 48mm x 3m Silver.

Please let me know if you have any questions.

Mitchell

[andre999]

Your suggestion is really helpful. I had to remove the glue and the Masons tape which was a challenge.

I am happy with the result with the Bear Flashtac Tape.

Thank you very much @MitchellMc .