Root barrier broken into sections - will it still work?

[BewareTheBeardedDragon]

I am intending to put root barrier along the boundary between me and neighbour, but have realised that if I put it directly under the fence, as I had intended, I will have to break it into sections because the fence posts are concreted into, so I can't sink it directly under the Feb e where the posts are.

So now I see that I have two options:

A) sink it in sections directly below the fence with a break of about 20-30cm width at each fence post.

B) sink it at a distance of maybe 10-30cm into my garden in a continuous run.

I want to prevent neighbours shrubs competing with my new fruit trees for water/nutrients, and to stop the ingress into my garden of their ivy, bamboo and sumac.

Which is the better option?

I'd say a continuous run, as otherwise the roots will just hit the barrier and grow sideways along it. They will inevitably find the gap.

Good luck with trying to stop bamboo though.

Thanks, I've been digging the trench today, 15cm in from the fence, in heavy and wet clay. It is a hellish task. It will be a continuous run. Fingers crossed it's worth it!