How to attach guttering without fascia?

[mocfan]

Hi all.
looking for some guidance please on best way to attach guttering to rafter ends where there is no fascia board  (attached picture).
thanks in advance

cheers

 

[MitchellMc]

Welcome to the Bunnings Workshop community @mocfan. It's brilliant to have you join us, and many thanks for your question about installing guttering.

The important point to start with is that the back edge of any gutter must sit under the roofing sheet so the water running off the roof can fall directly into it. In your photo the rafter ends sit very close to the end of the sheets, and that means that even if you fixed gutter brackets straight onto the rafter ends, the gutter would sit too far out. Water would drip off the roofing and fall behind the gutter instead of into it. That is why the setup you have now makes it difficult to attach guttering in a reliable way.

To make the gutter sit in the right position, the rafter ends generally need to be trimmed back to create enough clearance for either a fascia board or a solid mounting surface for gutter brackets. One option is to cut the rafters back so they finish close to the last roof batten, then fix your gutter brackets onto the newly trimmed flat ends. This only works if the rafter ends give you enough surface area for a bracket to be screwed on securely, and in many cases they do not. The more reliable approach is to cut the rafters back far enough to allow a fascia board to be installed, then mount the gutter onto that fascia in the normal way. That gives you the correct spacing and the correct fall, and ensures the gutter can sit under the roofing sheet as it should.

You can also go further and trim the rafters back almost flush with the lower beam they sit on, then install a full fascia board and gutter system from there. In every scenario some modification to the rafter ends is required, because with the current configuration there is simply no room to mount guttering in the correct position for it to function properly.

Let me tag @Nailbag and @AlanM52 for their thoughts.

Please let me know if you have any questions.

Mitchell
 

[mocfan]

thanks heaps - that is really helpful and practical advice.

By trimming the rafter end back flush presumably this means back to level with the batton edge the tin is screwed into as opposed to the larger bearer the rafter is sitting on ?

Cheers

[MitchellMc]

Ideally, trimming back to the baton should give you enough room to attach brackets @mocfan. However, not only do you need enough room on the end of the rafter to attach the bracket, but there also needs to be enough room to stagger the brackets down, allowing you to achieve sufficient slope on the gutter for the required fall.

Mitchell

[mocfan]

Thanks again - I suppose a trim back to baton would allow for a facsia to handle the fall issue.

One other question if I may - what is the minimum recommended overhang of the roofing sheet into the gutter to stop leaking behind the gutter ?

Cheers & greatly appreciated

Mark

[Noyade · Accepted solution]

G'day @mocfan 

AI says between 25-50 mm...

[Nailbag]

Hi @mocfan 

I pretty much agree with all the steps and comments @MitchellMc has already made. Just to add, I think the existing rafter will fall to short once cut squared off due to the large backwards curve as per @Noyade extract on specs. So, I think you will most likely need to attached a short length of board to the side of each one that the facia would actually attach to. Off-cuts from the facia board would be ideal and then liquid nailed and batten screwed to the rafters.

Nailbag

[AlanM52]

Hi @mocfan,

I think you will be OK to cut back and install the fascia with a margin for the fall.

Cheers

[mocfan]

Thanks heaps !!