Smurf in the Slab

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Gary11734

Gary11734

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Florida
Guys,

I'm doing a new Hotel in DisneyWorld. They are using smurf in the slab. I'm a EMT guy working in the past in conventional decks. This is a post tension slab at 8" thick. Trying to stay away from the finishers, I need to prop the smurf up with a PVC coupling that will be flush at the 8" mark. If not, the finishers will destroy the smurf. Any have experience with this pipe? Does caddy or anybody else have a way to prop this stuff up so it comes right to the 8" level, and stays in place? I'm running 1" and 1-1/4 smurf for fiber and electric. I'll be running two and three conduits per stub up... Not sure if I'll use gutters at the Panels are not.... Still thinking about it... Also, considering going down and down in the slab at panel and switch Home run to stay away from all this hassle... Also, I can't penetrate the deck...

Thanks for the help

Gary
 
you mean ENT, right? i dont follow installing the "8" flush"... the detail sheets should show that dead center of the slab is the only thing the engineers will approve- too close to the bottom or top of slab will weaken it as well as large amounts of ent bundled together (unless its at a box or panel)

use ENT stands and tie wire. as in, a ton of stands so you don't get floaters. they come in all the heights you need and screw into the forms

edit- and.... this would be a grand example of pre-fab- get the wires in first, or at least before they pour. the math is in the plans :)
 
rambojoe said:
you mean ENT, right? i dont follow installing the "8" flush"... the detail sheets should show that dead center of the slab is the only thing the engineers will approve- too close to the bottom or top of slab will weaken it as well as large amounts of ent bundled together (unless its at a box or panel)

use ENT stands and tie wire. as in, a ton of stands so you don't get floaters. they come in all the heights you need and screw into the forms

edit- and.... this would be a grand example of pre-fab- get the wires in first, or at least before they pour. the math is in the plans :)
Click to expand...
I'm with you - I don't see it being possible to get 1" or 1.25" raceway of any kind in center of 8" slab and turn up and put a coupling flush with top of slab, radius of bends is too much to do so.
 
Any way to get extra-long couplings that can stick up above the finished surface and be cut down to the deck once finished??
 
i now see.. he's looking for a way to protect the raceway at the turn ups/stub ups. well if they want to start a huge back charge war- the wrong concrete guys are on the job. if you are turning up in stud walls and air chases- screw em. they know damn well how to avoid it.

i would not transition the stuff. aside from a safety cone or a huge pvc pipe protecting the stubs, i dont know. this stuff is usually discussed at the foreman meetings, are they not? "hey, so, if you destroy my stuff you will kinda sorta have to do the whole floor over. Thanks!" another reason for pre pulled wires with a string...

they do make ent 90s/turn ups,downs- what ever, that screw to the form. they come presealed with paper too to keep out the mud but for hitting the laser mark at finished slab you would be building alot of stands. can you run your circuits the floor above? when the 90s are screwed in, they are pretty strong... but as you will see, they are not the greatest to pull through post pour.

edit- needing finish shot via the concrete guys sure becomes a nightmare for every dang turn up. money and time on both ends...
 
Gary11734 said:
I need to prop the smurf up with a PVC coupling that will be flush at the 8" mark. Does caddy or anybody else have a way to prop this stuff up so it comes right to the 8" level, and stays in place?
Click to expand...

This picture will explain what he's trying to accomplish. The top of the solvent-welded Sch40 PVC coupling must be flush with the finished surface of the concrete (which is 8" thick).
ENT2.jpg
 
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I'd probably use a PVC elbow, more rigid and easier to hold in place, or someone mentioned there is an ENT product out there for this.

Still don't see it working that you can have a coupling flush with the surface though, especially 1" or 1.25" raceway in 8 inch slab and maintain keeping the raceway run in center of the slab.
 
kwired said:
Still don't see it working that you can have a coupling flush with the surface though, especially 1" or 1.25" raceway in 8 inch slab and maintain keeping the raceway run in center of the slab.
Click to expand...
In the Carlon ENT Application Handbook, for embedding ENT in concrete they have the following recommendation:

The installation of Carlon ENT isn’t any different than theinstallation of comparable metallic conduit in a slab. ENTis installed on the first layer of rebar.The ENT is tied to therebar every 3 feet with duct tape, tiewraps or tiewire.Thiswill prevent floating of the ENT and hold it in positionduring the pouring of concrete.​

If it's on the first layer of rebar, then it's not in the middle of the slab. In any case, the engineered plans should specify where the ENT is to be embedded in the concrete. And presumably, they accounted for the bend radius when setting the depth.
 
Jon456 said:
In the Carlon ENT Application Handbook, for embedding ENT in concrete they have the following recommendation:
The installation of Carlon ENT isn’t any different than theinstallation of comparable metallic conduit in a slab. ENTis installed on the first layer of rebar.The ENT is tied to therebar every 3 feet with duct tape, tiewraps or tiewire.Thiswill prevent floating of the ENT and hold it in positionduring the pouring of concrete.​

If it's on the first layer of rebar, then it's not in the middle of the slab. In any case, the engineered plans should specify where the ENT is to be embedded in the concrete. And presumably, they accounted for the bend radius when setting the depth.
Click to expand...

Still not certain you can get a 1 inch raceway in an 8 inch slab and turn up to a coupling that is flush with the top without having the run darn near the bottom, 1.25 inch raceway only gets harder to accomplish.

How much tighter radius than what you see of a typical PVC elbow is NEC compliant? Those alone have to take up nearly all 8" of the slab thickness, and you still need a coupling on top.
 
kwired said:
Still not certain you can get a 1 inch raceway in an 8 inch slab and turn up to a coupling that is flush with the top without having the run darn near the bottom, 1.25 inch raceway only gets harder to accomplish.

How much tighter radius than what you see of a typical PVC elbow is NEC compliant? Those alone have to take up nearly all 8" of the slab thickness, and you still need a coupling on top.
Click to expand...
You are correct. For ENT...

362.24 Bends — How Made. Bends shall be so made that​
the tubing will not be damaged and the internal diameter of​
the tubing will not be effectively reduced. Bends shall be​
permitted to be made manually without auxiliary equipment,​
and the radius of the curve to the centerline of such​
bends shall not be less than shown in Table 2, Chapter 9​
using the column “Other Bends.”
​

Referencing Table 2, the "Other Bends" radius for 1" conduit is 6" and for 1-1/4" conduit is 8". The solvent-weld couplings lengths are 2" and 2-1/8" respectively.

Now I'm curious to see the blueprints. Direct burial is not permitted, so the smurf cannot be placed below the slab. It seems that either the engineer goofed, or someone decided to install larger conduit than what was specified.
 
rambojoe said:
you mean ENT, right? i dont follow installing the "8" flush"... the detail sheets should show that dead center of the slab is the only thing the engineers will approve- too close to the bottom or top of slab will weaken it as well as large amounts of ent bundled together (unless its at a box or panel)

use ENT stands and tie wire. as in, a ton of stands so you don't get floaters. they come in all the heights you need and screw into the forms

edit- and.... this would be a grand example of pre-fab- get the wires in first, or at least before they pour. the math is in the plans :)
Click to expand...

Ive been looking for ENT stands... haven’t found them yet... It’s an 8” slab and they don’t want any ENT above the pour when the concrete finishes start their machines... so, I need to stub up flush at eight inches or lower... I’m thinking going down, down so i don’t screw with the stub up issue... down down meaning the home runs are above the panels and coming out of the ceiling to a switch for the homerun in the suite. Yes, working on the CAD right now and trying to stay away from the cables... This slab will be loaded since they want it all in the slab. And no common neutrals so more pipe! Plus, 1-1/4 to each suite for fiber.... I hate post tension!
 
a fine example of one trade pressing a product gaurantee stipulation while screwing another trades ability to keep cost in check (ie using the spec wiring method). mean while, i bet every other trades bolck outs will not be flush... granted, its not too hard to plug the ent to facilitate flush stubs- it will just raise the time for each stub... in which case a strut would work which is the norm and tie wire your ent to it. these high rise slabs really arent too bad, the productivity will go up as it always does as the job goes along... just slap it all in fast and worry about the time consuming flush work after all the PT cable and wire mesh is in, then you will have stuff to attach your strut to... more important to get all the boxes for the turn downs against the form for the floor below FIRST. box it all BEFORE the post tension crap- then pipe it after... only reason id moan is id want the wire in place but cant always get what you want. nothing like a pita job that you can turn around and learn something- and make money off of...you will.

edit- and like i said, do some head scratching and try to split up some things from above, depending on how you want the panel raceways to go... since you have feeders occupying the bottom of your panels- maybe power in the cieling and data/com/fa in the floor... the data stuff isnt as critical as our power transitions. the ent 90s work quite well when screwed to a form... and are threaded. id post a link but im not that smart. just ideas. these kind of time saving stuff is what i kinda like about our trade. youll be suprised what your crew may come up with...
 
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Gary11734 said:
Guys,

I'm doing a new Hotel in DisneyWorld. They are using smurf in the slab. I'm a EMT guy working in the past in conventional decks. This is a post tension slab at 8" thick. Trying to stay away from the finishers, I need to prop the smurf up with a PVC coupling that will be flush at the 8" mark. If not, the finishers will destroy the smurf. Any have experience with this pipe? Does caddy or anybody else have a way to prop this stuff up so it comes right to the 8" level, and stays in place? I'm running 1" and 1-1/4 smurf for fiber and electric. I'll be running two and three conduits per stub up... Not sure if I'll use gutters at the Panels are not.... Still thinking about it... Also, considering going down and down in the slab at panel and switch Home run to stay away from all this hassle... Also, I can't penetrate the deck...

Thanks for the help

Gary
Click to expand...

schedule 80 pvc 90's, stubbed up above the deck. standard practice.
make sure they are wired solidly. finishers love to step on them and
force them below the concrete.

blow in string, stuff 5' extra down in the pipe, and cap with pvc caps,
not glued on. tap them on solid with kliens. if you glue them on, the
glue fumes kill the poly string, causing breakage later.

they can run finishing machines just fine around them, and hand finish.
this is non negotiable.

you *could* use a red dot 90, and do them that way.
if you do, you will deserve everything that happens to you. you've been
warned.
 
kwired said:
Still not certain you can get a 1 inch raceway in an 8 inch slab and turn up to a coupling that is flush with the top without having the run darn near the bottom, 1.25 inch raceway only gets harder to accomplish.

How much tighter radius than what you see of a typical PVC elbow is NEC compliant? Those alone have to take up nearly all 8" of the slab thickness, and you still need a coupling on top.
Click to expand...

The radius would be too great, I assume. Not trying to stub up above 3/4". Anything above 3/4", I take it as a down, down of both sides of the run. I also have some 2" in the deck. Since I can't penetrate, I will need to do a block out and attach at the ends at a later date.
 
Fulthrotl said:
schedule 80 pvc 90's, stubbed up above the deck. standard practice.
make sure they are wired solidly. finishers love to step on them and
force them below the concrete.

blow in string, stuff 5' extra down in the pipe, and cap with pvc caps,
not glued on. tap them on solid with kliens. if you glue them on, the
glue fumes kill the poly string, causing breakage later.

they can run finishing machines just fine around them, and hand finish.
this is non negotiable.

you *could* use a red dot 90, and do them that way.
if you do, you will deserve everything that happens to you. you've been
warned.
Click to expand...

Yes, I'm thinking pvc as the stub up. So you think Sch 80 in lieu of Sch40? This makes more since. And, the finishers will have to work around the stub ups like they have been doing for years. Trying to convince some that ENT was not sent from heaven is a problem. Once a supplier says you can save 40% labor costs, most stop listening and start buying.

My issue here is, you can't penetrate the deck. I don't like wondering if I can pull wire later in this stuff.

Are you saying the Red dot 90 is a disaster? It sure looks like it...

Thanks for the info...

Gary
 
rambojoe said:
i now see.. he's looking for a way to protect the raceway at the turn ups/stub ups. well if they want to start a huge back charge war- the wrong concrete guys are on the job. if you are turning up in stud walls and air chases- screw em. they know damn well how to avoid it.

i would not transition the stuff. aside from a safety cone or a huge pvc pipe protecting the stubs, i dont know. this stuff is usually discussed at the foreman meetings, are they not? "hey, so, if you destroy my stuff you will kinda sorta have to do the whole floor over. Thanks!" another reason for pre pulled wires with a string...

they do make ent 90s/turn ups,downs- what ever, that screw to the form. they come presealed with paper too to keep out the mud but for hitting the laser mark at finished slab you would be building alot of stands. can you run your circuits the floor above? when the 90s are screwed in, they are pretty strong... but as you will see, they are not the greatest to pull through post pour.

edit- needing finish shot via the concrete guys sure becomes a nightmare for every dang turn up. money and time on both ends...
Click to expand...

Hello,

I'm looking at those 90's that screw to the deck, but I'm concerned if I will get the wire in later. And this is post tension deck. The floating is going to be a problem... I can go down, down in the ceilings, but have an issue of pulling through those crazy 90's later. I can go up, up, but then the finishers are an issue.. Looks like stay on the ground and use PVC stub up at the present. Unless someone has a better idea?

Thanks all for the information.
 
rambojoe said:
a fine example of one trade pressing a product gaurantee stipulation while screwing another trades ability to keep cost in check (ie using the spec wiring method). mean while, i bet every other trades bolck outs will not be flush... granted, its not too hard to plug the ent to facilitate flush stubs- it will just raise the time for each stub... in which case a strut would work which is the norm and tie wire your ent to it. these high rise slabs really arent too bad, the productivity will go up as it always does as the job goes along... just slap it all in fast and worry about the time consuming flush work after all the PT cable and wire mesh is in, then you will have stuff to attach your strut to... more important to get all the boxes for the turn downs against the form for the floor below FIRST. box it all BEFORE the post tension crap- then pipe it after... only reason id moan is id want the wire in place but cant always get what you want. nothing like a pita job that you can turn around and learn something- and make money off of...you will.

edit- and like i said, do some head scratching and try to split up some things from above, depending on how you want the panel raceways to go... since you have feeders occupying the bottom of your panels- maybe power in the cieling and data/com/fa in the floor... the data stuff isnt as critical as our power transitions. the ent 90s work quite well when screwed to a form... and are threaded. id post a link but im not that smart. just ideas. these kind of time saving stuff is what i kinda like about our trade. youll be suprised what your crew may come up with...
Click to expand...


The thing will be a hybrid. I'm looking at all the options. Since the Electric rooms are every other floor to the stacked IDF, Some will be in the ceiling, some in the Floor...

I just finished the BIM for the first three floors which were not the typical suites. Now 349 units to figure how to run all this crap.
 
Gary11734 said:
The thing will be a hybrid. I'm looking at all the options. Since the Electric rooms are every other floor to the stacked IDF, Some will be in the ceiling, some in the Floor...

I just finished the BIM for the first three floors which were not the typical suites. Now 349 units to figure how to run all this crap.
Click to expand...

they pull fine as long as the string is there (and don't even think about 1/2"). if you do a "from to" with the pvc, just tape the heck out of the fittings. all im saying is they (ent 90s) aren't designed for slab stubs... but against the form, they are great. sounds like you have hard lid every where, right? including your own access doors means you can use ent to taped up 4sq's for a few things....then ext...
 
ps, if there are expansion joints in the slab (which I hope you don't) you will have a little more head scratching to do.. it will have to stub out, then back in the slab.... :)

having pre pulled wire into boxes works great for the parking garage lights- then you can use it for the temp lights. and of course, don't forget block outs for the temp power in the hotel part! its a pleasure to share tips.
 
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