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tommy_gunne
drilling thru floor joist

So for a 2 by 8 floor joist, what is the largest hole you are allowed to drill through it, and do they make flat bracing for larger holes(ie, more of joist removed)?

canuk
Re: drilling thru floor joist

Holes can't be larger than 1/3 the depth of the member and not closer than 2 inches to the top or bottom of the member.

So for a 2x8 that equates to a hole of 2.5 ( 2.49) inches.

Here's a thread that discusses this issue: http://advice.thisoldhouse.com/showthread.php?t=5798

tommy_gunne
Re: drilling thru floor joist
canuk wrote:

Holes can't be larger than 1/3 the depth of the member and not closer than 2 inches to the top or bottom of the member.

So for a 2x8 that equates to a hole of 2.5 ( 2.49) inches.

Here's a thread that discusses this issue: http://advice.thisoldhouse.com/showthread.php?t=5798

Thank you, CANUK!!

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