# Preferred boxes for concrete walls



## sbrn33 (Mar 15, 2007)

I would use a masonry box.


----------



## masonc (Nov 6, 2012)

That's exactly the advice I wanted. I get lost in all the different box configurations, especially as we don't normally bid the rough in work.


----------



## sbrn33 (Mar 15, 2007)

The ones I use are gangable. I will try to get a ic if I get a chance. Hndi box is to small and anything else will get **** in the threads.


----------



## masonc (Nov 6, 2012)

sbrn33 said:


> The ones I use are gangable.


I have used them, and they are very cool, but I have also seen specs that prohibited them. As we know the configurations, I can just order the right ones now. Gangable are great to hold in stock for those difficult situations.


----------



## John Valdes (May 17, 2007)

I did high rise slab work and rough in on tall condo units and everything was 1900 boxes and rings.
If you have the ability to be on site while the walls and floors are being constructed, there really is no big reason to go with special boxes.
Of course we used concrete rated deep octagons for ceiling lights that were embedded in the slab. But the walls inside and outside were always just 1900 with rings.
Everything for each floor was prepped in the shop with connectors installed and fully taped up. We even made stubs during rain days and such to alleviate so much bending up there in the hot sun.
The company really had this stuff figured out. The material box/gang box was flown (lifted with crane)to the floor under construction and everything required for that floor was included. Ready to go.


----------



## MechanicalDVR (Dec 29, 2007)

Always used Raco 690 series or Steel City MB series boxes for new concrete construction.


----------



## cabletie (Feb 12, 2011)

Almost always 4"sq with tile rings. Most of the time you may want two conduits entering the same side of the box, but only need a single gang. 

I am not sure of your situation, but usually you have two conduits coming up from below into a single device.


----------



## telsa (May 22, 2015)

Duct tape sealing standard 4 squares + deep plaster rings &&& with tie wire reaching through the back side to the front -- tied and twisted around a micro stub of 1/2" EMT to strap it during the wet mortar period...

The PVC enters and exits from the bottom -- some times the top. (rare)

That's the commercial solution I've seen all around here.

Every outfit is doing it that way.

The tie-wire bit FORCES the P ring to be square and flush to the cinderblock.

If an additional layer is to thicken the assembly -- then the EMT stub has shims wedged between the cinder block and the EMT forcing it to protrude all the way.

The opening is usually duct taped, as well, the cavity stuffed with wadded newspaper.

You get the idea -- this is all shop prepped -- rain days -- off hours -- apprentices.

The T/As are already secured to this assembly.

Spares are stocked -- for screw ups -- not a whole lot -- just some.

It's wise to LABEL them -- per the scheme -- so that, in the rush, the right box is used.

Here and there, the box is upgraded to a 4-11. ( rare )

In my experience, these boxes face the exterior of the structure -- and are set at receptacle heights for vending machines and such.

If they face the interior ( rare, for us ) you have to stay on site and baby sit the progress of the masons. That'll be lots of fun. :no:

I can't speak to multi-story builds, as cinder block is not popular in earthquake country for multi-story habitation.


----------



## MechanicalDVR (Dec 29, 2007)

telsa said:


> Duct tape sealing standard 4 squares + deep plaster rings &&& with tie wire reaching through the back side to the front -- tied and twisted around a micro stub of 1/2" EMT to strap it during the wet mortar period...
> 
> The PVC enters and exits from the bottom -- some times the top. (rare)
> 
> ...



I have not been on a job where they used pvc conduit for the in wall conduit runs. Funny you mention 'babysitting', I have never been the guy to do this but i have seen the guys doing this many times. They were armed with a bundle of 30" sections of EMT with a coupling attached to one end to go up as the masons progressed. It also occurs to me that many of the runs just go to a height above the finished ceiling height and all the wiring is basically run overhead with little if any in the slabs.


----------



## fistofbolts (Jan 25, 2014)

Babysitting the masons was one of my least favorite jobs on one project.


----------

