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Walker duct

25K views 17 replies 8 participants last post by  Wirenuting  
#1 ·
I have a project coming up where there is exsiting Walker duct in a concrete floor. I need to add a few receptacles in a new area using the duct.

Not being very familiar with this stuff, I'm not sure how to approach it. Do I just core drill the concrete until I hit the duct and then hole saw it?

I'm really concerned about the exisitng conductors and not damaging them. Any insight would be great.

Thanks
 
#10 ·
Walker Duct Tooling

An easy way to safety and efficiently install new electrical flush mounted boxes to concrete covered Walker Duct (underfloor duct) is to use a special device that drills concentric holes with a diamond bit for the concrete and an inner mounted carbide core bit for the smaller hole in the steel duct. A video showing the correct equipment can be seen on the Diamond Tool .net website or by calling them.

Ed Kelley
 
#11 ·
I forgot the spacing on walker duct.
But I believe Walker went out of business in the early 80's?
Look in the access panel for the low voltage side, a model number should be there.

The picture bob posted is square D?? Never seen a 3 bank duct.
 
#15 ·
I came across one of these things that was incorrectly installed this summer. The duct had no cups on top....and the knockouts were buried under 5" of concrete. We had to do exactly what the OP said, core drill the concrete then use a diamond hole saw for the steel plate. It was a scary situation, made me wonder if that duct was a homemade thing and snuck in before the inspector got a chance to see it
 
#16 ·
Rollie73 said:
I came across one of these things that was incorrectly installed this summer. The duct had no cups on top....and the knockouts were buried under 5" of concrete. We had to do exactly what the OP said, core drill the concrete then use a diamond hole saw for the steel plate. It was a scary situation, made me wonder if that duct was a homemade thing and snuck in before the inspector got a chance to see it
When ever we had to fill them without the cups, we put some paper then a light layer if Pour-Rock.. You could find them by tapping on the tile floor. The pour-rock broke up easy and vacuumed out.
 
#18 ·
Rollie73 said:
I wish the original installer had done something like that. It was my first time dealing with it and it wasn't a pleasent experience:no:
The original installer I would think did use the proper cups and marking screws.
We didn't have access to them at the time of removal.

I have used a cheap metal detector to find the screws below the floor tile.
After the first one the rest are even distances apart and next to each other.

Write down in the low voltage panel were the first cup is,,,, please