Conduit Support

[Duncan Bennett]

Looking for some advice if anyone can help.

I've been asked to install sockets in a new build business unit. The company deals with software imaging - lots of computing power but no machinery, tools, etc.

The place is pretty much a standard build with a number of heavyweight vertical RSJ's cross-hatched with U-shaped, mild steel beams onto which a potential plasterboard wall could be fixed. The client is leaving this open, though, so I was hoping to hole-cut through the steel beams and run a 20mm plastic conduit through from one end to the other in an L-shape from the CU on one wall a total length of around 20m.

I'm running a radial circuit for four twin sockets as they are all being placed on this one run. Trouble is, the regs say that rigid plastic conduit has to be supported at 1.5m intervals for a horizontal run, and there's approx. 2m space between these. So, i'm considering fixing a 3x1/2" wooden plate along the length of the wall on top of the steel uprights and then fixing the conduit to that. Steel conduit or tray are options, but I'm trying to keep the price as keen as I can. Can anyone suggest another method?

Thanks

 

[Jay Sparks]

Without seeing the install, I think useing a piece wood for the fixings sounds ok. Although, I dont think it would be a big problem if the fixings were every 2m instead of 1.5m.

Jay

 

[Duncan Bennett]

Without seeing the install, I think useing a piece wood for the fixings sounds ok. Although, I dont think it would be a big problem if the fixings were every 2m instead of 1.5m.

Jay

Cheers, Jay.

I'm just a bit concerned that the conduit will be hanging in open air inbetween the uprights; wouldn't be so bad if they were going to be covered in plasterboard, but the customer is leaving the wall open, so there is always the chance that some gormless individual will use the conduit to support themselves while they tie their shoes :-/

Just thought there would be another method?

 

[telectrix]

use steel trunking or steel conduit. and i'd be wary of drilling through structural steel.

 

[Duncan Bennett]

use steel trunking or steel conduit. and i'd be wary of drilling through structural steel.

That was another concern, Telectrix, but on looking at the structure, the steel isn't really supporting anything; it appears only to provide a support for the fixing of the outer (tin plate) walls, and the (potential) internal plasterboard / composition walls.

On the face of it, though, I think I'll quote for the wooden plate; it'll give me good fixings for both the conduit and the sockets.

 

[telectrix]

doesn't the steel support the roof girders and hence the roof?

 

[Duncan Bennett]

It doesn't appear so, Telectrix; The main RSJ's are bolted to cross members which the roof is attached too, the internal steel work is definitely not capable of taking that sort of weight.

 

[Des 56]

You have good support at your feet if its possible,the floor?

 

[tigerpaul]

Don't forget, the plastic conduits will be heavier with the cables in them and will sag down... Not a good look really.
I'd suggest steel, keep it tidy, it won't flop about when and if it ever gets cleaned either.

 

[tigerpaul]

Also, get clarification on drilling the steel, you don't want to ruin the integrity of the structure.

What about using caddy clips to hold the steel conduit up?

 

[Duncan Bennett]

You have good support at your feet if its possible,the floor?

What do you suggest, Des?

 

[Duncan Bennett]

Don't forget, the plastic conduits will be heavier with the cables in them and will sag down... Not a good look really.
I'd suggest steel, keep it tidy, it won't flop about when and if it ever gets cleaned either.

Only running 2 x 4mm singles and a cpc but, yeah, it's not a good look is it - and certainly not going to be rigid :-(

 

[Des 56]

What do you suggest, Des?

Almost impossible to say without seeing the place,but if conduit can't be supported,therefore ditto tray
Swa on the floor, or conduit dressed around the pillars,metal trunking will give its own support to an extent,that has sometimes been my own decisions occasionally when some self support was needed

 

[alarm man]

id ditch the plastic and go galv,will look better and more suited to the job,as tiger said used beam clips to support

Buy Newlec Horizontal Conduit Beam Clip. 19mm - 26mm Diameter, Grip 8mm - 14mm - NLAH814A

 

[somersetsparks]

Id' certainly go with galv tube, Plastic may look ok now but give it ten years? The spacings in BS7671 are the maximum spacings and way, I would say plastic should be supported more like every 3' in honesty.