Ask a question

The Bunnings Workshop community can help with your home improvement projects.

How to close the gap between pergola and roof?

Just Starting Out

How to close the gap between pergola and roof?


We have recently had someone build us a pergola, which is amazing. However, when it rains, the water flows back towards the house and spashes on the iron roof which then splashes over the gutter which wets under the pergola area a lot. Just looking for an idea to block off the gap in the photo so the water won't splash and should just flow into the gutter leaving it dryer for the dogs. 

Thank you in advance for reading and for any suggestions you may have :smile: 


Having an Impact

Re: How to close the gap between pergola and roof?

Hello brydee,Just looking at your pergola and can see how heavy rain would be a problem if the fall on the pergola roof is towards the house as you mentioned,and both roofs  are sharing the gutter on the main roof.I can't see but I don't think the new pergola roof has it's own gutter,so the rainwater would just drop over onto the house roof. Maybe if it had a gutter with a couple of "spreader" downpipes feeding onto the main  roof it would slow the flow down and stop the initial splashing, but it looks like the downpipe on the house gutter also has another downpipe feeding into it as well,so it probably has trouble coping with really heavy downpours.As for the gap,maybe the fellow who built it might be able to rig up a bit of purpose cut zincalume sheeting fixed to a few droppers to cover it.Probably haven't been much of a help brydee,but maybe a couple of things to thing about at least.Regards Terry.

Bunnings Team Member
Bunnings Team Member

Re: How to close the gap between pergola and roof?

Hello @brydee 


Welcome to the Bunnings Workshop community. It's splendid to have you join us, and thank you for sharing your question about closing the gap on your roof.


One way to stop the rain from going on to the steel roof is to attach another gutter onto the falling side of the pergola. However, I strongly recommend that the outlet for that gutter be attached independently so that it does not overwhelm the one currently attached to the lower roof.


Another approach would be to attach Suntuf 3.6m Clear Greca Polycarbonate Sheet onto the falling side of the pergola. The sheet will need to be cut into sections and placed as close as possible to the roof. This will serve as a barrier to the water hitting the iron roof. I've placed a sample sketch below to give you an idea of how to cover the gap.


Let me call on our experienced members @TedBear and @diy_hausdesigns for their recommendations.


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





See something interesting? Give it the thumbs up!
Kind of a Big Deal

Re: How to close the gap between pergola and roof?

Hi @brydee , in addition to suggestions already proposed, I'd suggest considering using some zinc flashing, painted a dark colour to blend in with the timber, attached to the back of the timber backing of the pergola. It would fill the gap (or most of it) and direct any drips from the pergola roof onto the house roof, well back from the gutters. 

(Attach it to the back board of pergola only, to sit just above the house roof metal.)


Why join the Bunnings Workshop community?

Workshop is a friendly place to learn, get ideas and find inspiration for your home improvement projects