1st Cable Tray Job

[chris_k]

Evening.

Ive got my first job involving a bit of cable tray coming up.

It is to support the feeds to 2 flats that rise up in the corner of the stair well. They then need to run along  the centre of the hallway ceiling and jump into the front of the flats. Off this tray will be the lighting and smokes. I plan on supporting the 225mm tray on slotted channel and m10 threaded rod. The problem is the ceiling ive got to mount to is made of hollow clay / pot blocks. Anybody know of a suitable method of mounting into this kind of material?

 

[Essex1]

Instead of fixing the rod straight into the ceiling install some Unistrut than hang the rod from zebs. This way you have a number of oportunities to get a secure fixing for the Unistrut.  

 

[Evans Electric]

Like Joey says , drill a few holes in your unistrut so you can pick up the sounder fixings .

M10 rod might be overkill , not seen the job but how about M8 rod .  You can hang a battleship from an M10 rod.

 

[steptoe]

As @Essex1 said, and, if the blocks really are that hollow, which I doubt, you can get some resin fix, it's in a tube a bit like gripfill, but it's a twopart mixed setting compound, self mixes in the right quantities as you use it, stick your unistrut fixings into it before it goes off,.

Like Joey says , drill a few holes in your unistrut so you can pick up the sounder fixings .

M10 rod might be overkill , not seen the job but how about M8 rod .  You can hang a battleship from an M10 rod.

Or even M6,,,,  

Always makes me laugh when you see M10 rod used for the tray, and 1&1/2" 8s used to fix the unistrut,,, :C

 

[chris_k]

judging by the amount of holes the suspended ceiling guys previously have made when trying to get a fix it should be fun.

The blocks are defiantly hollow. ive test drilled a few holes. The tray will be holding 2x 25mm 3c swa, a couple of 4mm twin and skin and smoke feeds. You think 8mm would be ok?

 

[Andy™]

6mm would probably be more than enough. as rodney says, there is usually a lot less holding the unistrut to the ceiling than the tray to the strut

 

[M107]

Can you not move the tray location & use wall hangers for a better fixing?

 

[sprocketflup]

Sky hooks.

 

[steptoe]

judging by the amount of holes the suspended ceiling guys previously have made when trying to get a fix it should be fun.

The blocks are defiantly hollow. ive test drilled a few holes. The tray will be holding 2x 25mm 3c swa, a couple of 4mm twin and skin and smoke feeds. You think 8mm would be ok?

What's twin and skin,???

:C

Stick it up with gripfill,

Most handymen do,,,,   :|

 

[Davethsparky]

I've had dealings with these hollow clay block constructions before, there is usually a very narrow band of solid concrete between the blocks.

the best thing to do it fix to the wall as mentioned above, some unistrut cantilever brackets would do nicely.

 

[M107]

Beat me to it Steps.......................... :slap

 

[sprocketflup]

Hollow blocks? Spit gun then

 

[steptoe]

Hollow blocks? Spit gun then

Probably burst them,

I tried that once on bison units,

Left a load of inch holes in them, 

Maybe red cartridges were too heavy, but I only had them or black, :|

Black would prob have went through the top as well,

 

[sprocketflup]

maybe I should have used the wink smily

 

[steptoe]

Maybe,

 

[M107]

http://www.fischer.co.uk/PortalData/10/Resources/support/substrate-reports/documents/Wienerberger_report_march_2010_AW.pdf

 

[Essex1]

https://www.hilti.co.uk/masonry

https://www.hilti.co.uk/medias/sys_master/documents/h9b/9106719866910/ASSET_DOC_2331209_APC_RAW.pdf

https://www.strongtie.com/adhesives_anchoringsystems/category?v=%3Arelevance%3AfeatureApplicationMenuFacet%3AConcrete+Block%7C%7C+Hollow+%28Ungrouted%29

https://www.strongtie.com/screentubes_adhesiveanchoringaccessories/optimesh_screentube/p/opti-mesh-adhesive-anchoring-screen-tubes

You will not get better than Hilti Hit 

 

[sprocketflup]

You will not get better than Hilti Hit 

careful now, Kwik Fit may sue

 

[steptoe]

http://www.fischer.co.uk/PortalData/10/Resources/support/substrate-reports/documents/Wienerberger_report_march_2010_AW.pdf

That stuff at 3.4 ,  that's it, great stuff that, 

Someone on site once hung an apprentice from a hook just stuck into it, left him there for about an hour too, he didn't mouth off so much after that,,,, :slap

 

[Sharpend]

Wasn't you then!