Wires through joists

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rao.manoj2004
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Joined: Mon Oct 22, 2018 3:29 pm

Wires through joists

Post by rao.manoj2004 » Sat Nov 03, 2018 7:31 am

Hi Emtnut/Aaron/Sannon,

Good morning!!

I will be pulling my wires (not recepticals one) through ceiling and many would be perpendicular to joist (mean through joists). I have seen video of drilling holes in joist and then pulling wire through them. I want to know the ontario codes like
- hole size and whether hole need to be centered.
- how far each hole to any other hole in same joist
- how many wires per hole (14amp, 12amp, 10amp,8amp)
- Any other code I need to take care.

Thanks
joist_wires.jpg
joist_wires.jpg (12.5 KiB) Viewed 127 times


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Shannon
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Re: Wires through joists

Post by Shannon » Sat Nov 03, 2018 3:13 pm

For TGI joists like you have there are specs for holes here is a link to one manufactures recommmendations if you can tell who manufactured yours I would have a look for their specific guild.
https://www.weyerhaeuser.com/woodproduc ... l/tj-4000/
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emtnut
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Re: Wires through joists

Post by emtnut » Sat Nov 03, 2018 7:26 pm

rao.manoj2004 wrote:
Sat Nov 03, 2018 7:31 am
Hi Emtnut/Aaron/Sannon,

Good morning!!

I will be pulling my wires (not recepticals one) through ceiling and many would be perpendicular to joist (mean through joists). I have seen video of drilling holes in joist and then pulling wire through them. I want to know the ontario codes like
- hole size and whether hole need to be centered.
- how far each hole to any other hole in same joist
- how many wires per hole (14amp, 12amp, 10amp,8amp)
- Any other code I need to take care.

Thanks

joist_wires.jpg
x2 for what Shannon said. They will be the ones to let you know exactly where, and what size to put the holes.
This is a typical example (see pic.

As far as how many wires. The rule of thumb is 2 cables per hole. What you want to avoid is 'bundling' of cables, where you would have to derate the ampacity.
I usually use a 9/16" or 3/4" spade bit for the holes.
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!joist-holes.jpg (40.84 KiB) Viewed 110 times
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rao.manoj2004
Posts: 19
Joined: Mon Oct 22, 2018 3:29 pm

Re: Wires through joists

Post by rao.manoj2004 » Sun Nov 04, 2018 9:48 pm

Thanks Shannon/Emtnut. I see that current wiring through joist have 2 wires in each hole. I will follow the same.

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