LED Decking Lights. Transformer Inside Garage, Cable Outside. Hidden or Not

[Door7000]

I will be installing composite decking and would like to add like LED lights like this one:

https://www.nationallighting.co.uk/ikon-pro-cct

I chose this type because the bulbs can be changed individually if blown, rather than having to take the whole lot up.

The wiring looks like this:

The decking is next to the garage so I am considering having the transformer in the garage plugged into the existing free socket (it's RCD protected). The 5m cable (in the middle of the diagram) would go through the wall and into the deck frame.

1. Should I run the 5m cable through the garage wall with enclosures on each side and trunking where it is exposed from the outside enclosure to the deck frame?

2. There is a 12cm gap between the garage wall and the decking. This will be filled level with slate. Is it OK to run the cable below this level and also the DPC level so that it goes directly into the deck frame thus totally hidden from view? Note the point that the DPC would be pierced with something like a 10mm drill, advice on this?

3. Would I need trunking in the deck frame or is it ok for the cables to be cable clipped under the deck joists (which are raised off the ground)?

 

[oldbutnotdead]

The ELV cable coming out of the garage, if it is intended for outdoor use (uv stable) doesn't have to be hidden from sunlight and rain. Good idea to use conduit or similar through the wall and wherever it would be susceptible to knocks (from garden tools, furniture etc).
Going under the slate i'd use a bit of conduit again (again to prevent any chafing from the slate ) but you don't have to.
Under the decking clipped is fine (as long as it is outdoor uv stable cable). Good luck clipping anything to composite though