50mm trunking in wall

[gm68]

Monday

Thank you so much for your post! Exactly what I've been looking for is an informed opinion from a structural engineer rather than an electrician.

My lounge is located on the corner of the house with 2 external walls, the side one of which is the one that has been chased. So it is the inner leaf of a cavity wall.
I was hoping to go a bit beyond standard steel conduit and put in square section 50mm x 50mm tubular steel reinforcing bar, with the cables run up the middle. I can get this fabricated from 5mm thick steel. I will fill around it with cement as you suggest.

What's most reassuring is that I had some discussion earlier with a structural engineer, explaining in detail what I had done, and his answer was exactly the same as yours.

 

[monday]

Glad this has been useful. I guess the size of conduit depends on how much cabling you need to put through it. Standard conduit is pretty chunky stuff and would be a lot cheaper than fabricating your own - unless you know someone. Also 50x50 section in a 50mm chase isn't going to leave much room for the cement!

But if you need to go bigger, square hollow section (usually abbreviated to SHS) is available readymade in all sizes from about 20mm x 20mm upwards. Might be difficult to get in small quantities though but try for an offcut from a steel supplier.

Good luck.