Running Mc in concrete decked drop ceiling

[Flex]

I am running MC fixture to fixture in a drop ceiling with a concrete deck. I dont want to tapcon the mc with one holes to the concrete deck but I cant think of any other way to support the MC. The ceiling isnt up yet so I figured i get ahead of them. I thought about when shooting my fixture supports in the deck for the fixture tie ups maybe shooting extra to tie the MC to. Figured Id ask for some other ideas.

 

[electricalperson]

I am running MC fixture to fixture in a drop ceiling with a concrete deck. I dont want to tapcon the mc with one holes to the concrete deck but I cant think of any other way to support the MC. The ceiling isnt up yet so I figured i get ahead of them. I thought about when shooting my fixture supports in the deck for the fixture tie ups maybe shooting extra to tie the MC to. Figured Id ask for some other ideas.

would these be of any use http://www.arlcatalog.com/Flex/Steel Cable Hangers.htm

 

[Flex]

Nice find. If i had more than one cable to jump around they seem like they would be perfect. However I have only one 12-2 MC jumping around light to light. Looks like one-holes it is.

 

[ultramegabob]

I would probly just use one hole straps and a powder actuated nail gun.

 

[Flex]

Do I need a license?

 

[ultramegabob]

Do I need a license?

for what? the powder actuated nail gun? I dont where I live, you may want to check your local laws, it isnt a firearm...

 

[cadpoint]

With new concrete I'd go with a lead pin or a lead set anchor and drilled, the concrete won't be cured for a shoot! unless it's old construction...

See if you can get the PSI of the concrete it matters to the shoot.

 

[JFletcher]

Do I need a license?

Probably not, but you ought to get a safety certification for the specific tool you use. See OSHA 1926.302(e).

 

[iwire]

We would shoot it using a viper and ceiling tie wires that already have a pin connected to them.

http://constructionfastening.com/powder.html


Or if we want to use bridal rings we shoot these clips into the deck.

 

[ultramegabob]

With new concrete I'd go with a lead pin or a lead set anchor and drilled, the concrete won't be cured for a shoot! unless it's old construction...

See if you can get the PSI of the concrete it matters to the shoot.

I think his original idea of tapcons would cost less and be less labor intensive

 

[iwire]

I have no issue with green concrete just use the right charge. I will take green concrete over 100 year old concrete any day. That old stuff likes to blow out instead of holding fast.

 

[ultramegabob]

I have no issue with green concrete just use the right charge. I will take green concrete over 100 year old concrete any day. That old stuff likes to blow out instead of holding fast.

I will second that....

 

[ultramegabob]

Or if we want to use bridal rings we shoot these clips into the deck.

what do these bridal rings you would use with these clips look like? would there be a problem with just using tie wire to hold the m.c. up with those? I wouldnt do it out in the open, but he said it was above a suspended ceiling.

 

[jeremysterling]

Here in Austin, troffers are independently supported from the grid. We paint our ceiling wires yellow and shoot them up with the powder-actuated tool, either with a lift or pole-gun. We use 7/8" drive pins to stay shallower than the post-tension cables in the slab. Each troffer is required by municipal code to be supported on all four corners. We use a lot of MC "batwings".

I shoot additional wires and tie them to the grid for "batwinging" homeruns, switchlegs, emergency and nightlight ckts. The inspector looks to make sure all electrical is on yellow painted ceiling wire.

 

[iwire]

I don't see any real problem with just using tie wire and I do that often. :smile: But bridal rings are handy, easer to add cables to and I think the job can come out looking better.


http://www.erico.com/products/CADDYcfcFlexibleConduitCableHanger.asp

 

[ultramegabob]

I don't see any real problem with just using tie wire and I do that often. :smile: But bridal rings are handy, easer to add cables to and I think the job can come out looking better.


http://www.erico.com/products/CADDYcfcFlexibleConduitCableHanger.asp

I have never used that type of bridal ring before, all the ones I have used were screwed into beam clamps or had a wood screw tip on them, I will have to remember those, thanks!

 

[ultramegabob]

I shoot additional wires and tie them to the grid for "batwinging" homeruns, switchlegs, emergency and nightlight ckts. The inspector looks to make sure all electrical is on yellow painted ceiling wire.

I think he is wanting to get his cable up before the ceiling grid is installed.

 

[Doug S.]

With new concrete I'd go with a lead pin or a lead set anchor and drilled, the concrete won't be cured for a shoot! unless it's old construction...

See if you can get the PSI of the concrete it matters to the shoot.

Make sure lead / zinc / not steel is ok per your local code. Some folks don't like it, because the heat (fire) will melt the anchor ... ... ... and you get the point.

You can shoot into new concrete. The newer the better for the product that iwire showed. OLD concrete like's to make a mess when shooting into it...ack.


Just shoot it, you'll be happy and amazed at the labor savings.

 

[tim123]

We typically use the viper like iwire does. Trying to make massive vertical racks of mc and kx clips to cut down on labor. However from time to time we are not allowed to use that gun, something about the nail being to long and possibly hitting post tension cables. In that case we use a t3 nail gun, that usually blows the concrete out a bunch and makes for a rough couple of weeks.

 

[electricalperson]

We typically use the viper like iwire does. Trying to make massive vertical racks of mc and kx clips to cut down on labor. However from time to time we are not allowed to use that gun, something about the nail being to long and possibly hitting post tension cables. In that case we use a t3 nail gun, that usually blows the concrete out a bunch and makes for a rough couple of weeks.

what are post tension cables and what happens if they get hit?