Balustrade fixing through waterproofing details

[Adam2]

One area of my balustrade needs to cross an insulated concrete deck (200mm RC 45 deck). Above the deck is 160mm insulation (tapered). This balustrade is only to prevent over-looking of neighbouring gardens so stops access onto a flat roof area.

 

Am looking at details for how to secure the U channel down into the concrete. I figured maybe a steel U channel with welded on side fixings as the base - could insulate under the channel. This could be to the max height of the insulation, have fixing holes for U channel at 400mm centres running along this. The waterproof membrane could then run across the steel with holes for blind bolt fixings and some form of pipe waterproof fixing fitted over a small circular upstand to bolt the U channel down onto.

 

If anyone has a nice detail for this would be great to see before we finalise.