To fill or not to fill gaps between external oak 'beams'

[Wikisnoodle]

The entrance hall of my 4 year old bungalow extends into what is a 'porch' on other bungalows in the development. Externally this 'porch' is finished in tudor oak style. It's real oak, but 2'' planks around the panelling rather than proper beams.

There has been a fair bit of movement and I have used expanding foam overfilled with exterior flexible/paintable silicon between the panelling and the oak.

What should I use between the 'beams'? Should I use anything? The gap is often 2"deep, varying in width, but over 1" wide on the external corners.

 

[joe-90]

You should really cut slivers of wood and tap them in. I'd just leave it if you can't do that.

 

[Wikisnoodle]

Thanks for the swift reply. I'm not known for having any oak laying about. Perhaps a visit to a local specialist builder would locate some offcuts.