Wood to Concrete Slab sealant for Summerhouse?

Just finished building a Lugarde Summerhouse...



I want to seal around the outside of the tantalised foundation ring beam where it sits on the concrete slab base, as here...



...to stop water ingress under the foundation beam eventually rotting it (even though it's tantalised).

I'm thinking there are two Screwfix sealants which may do this job:

http://www.screwfix.com/p/sika-sikaflex-ebt-all-weather-sealant-clear-300ml/7286d

...this one says on the tube it's suitable for concrete and wood, but not that it's UV stable.

Or,

http://www.screwfix.com/p/no-nonsense-builders-silicone-clear-310ml/83710

...this one says on the web site it's suitable for concrete and UV stable, but doesn't mention if it's OK for wood.

Which one should I use, or something else? It needs to bond to wood & concrete, be waterproof, flexible, and UV stable.

Many thanks for any help!

PS. Inside, there is a Visqueen membrane to the slabs, floor bearers over, celotex insulation boards, then floor boards over.

 

Thanks for that, so Sikaflex has UV durability.

I wonder if the No Nonsense sealant is OK for wood? Should I be concerned it's less than half the price of the Sika?