3-3/4 in.The hole cannot be larger than one-third the depth of the joist, so the maximum hole size for a 2×12 joist (actual size 1-1/2 x 11-1/4 in.) is 3-3/4 in. diameter—plenty big enough for running cable! You can drill the holes anywhere along the length of the joist (first photo).

## What size hole do you drill for electrical wire?

Most electricians keep their inspector happy by drilling 3/4-in. holes dead center on a 3-1/2 in. wide stud. This gives them a hole large enough to run two electrical cables and leave 1-3/8 in.

## Can you drill holes in joists for electrical?

You can safely drill joists for electrical and plumbing runs without weakening the joists, if you follow the rules.

## How big of a hole Can I drill in a 2×6 floor joist?

You can put holes in floor joists anywhere along the length of the joist, but you can’t put them any closer than 2″ from the top or bottom edge of a joist. The maximum size of a hole is 1/3 the depth of the floor joist.

## How big of a hole can you drill in a 2×8 joist?

2 3⁄8 inches

In addition, the hole’s diameter is limited to one-third the depth of the material. In a 2×8, for example, the maximum hole diameter is 2 3⁄8 inches (actual rather than nominal dimensions should be used to make these calculations).

## What size hole can you drill through I joist?

1-1/2 in. diameter

You can drill the holes anywhere along the length of the joist (first photo). If you have manufactured I-joists, you can drill holes up to 1-1/2 in. diameter almost anywhere in the web area (the area between the flanges). Just stay 6 in.

## What are the codes for drilling or notching joists?

IBC 2308.8.

Notches on the ends of joists shall not exceed one-fourth the joist depth. Holes bored in joists shall not be within 2 inches (51 mm) of the top or bottom of the joist, and the diameter of any such hole shall not exceed one-third the depth of the joist.

## How do you run wires through joists?

The best way to run wires along ceiling joists is to use a running board, spacing the wires evenly with electrical staples. This is for running wires in the direction of the joists or perpendicular to them. If there is no space, you can bore holes in very specific places to run wires through.

## Where do you drill joists for cables?

Do not notch or drill holes through the top or bottom flange. It is generally permissible to drill up to 38 mm holes anywhere in the web. Typically, most manufacturers have little perforated knockout holes that can be punched out without the use of a drill.

## Can you drill through 2×10 joist?

The maximum allowable diameter of a hole in any solid-lumber joist is one-third of the joist’s depth. Notches can’t be deeper than one-sixth of the joist depth. In the case of your 2×10 joists, the maximum diameter is 35⁄64 in.

## How big of a hole can you put in a 2×6?

2″ x 6″ = maximum 2-3/16″ notch. BORED HOLES Maximum size hole = 60% of stud width: 2″ x 4″ = max. 2- 1/8″ diameter hole.

## Does screwing into a joist weaken it?

When weight is applied to a joist, the top edge goes into compression while the bottom edge goes into tension. Improperly sized or placed holes and notches weaken the joist, make it bouncy and saggy, and provide an easy place for it to crack and fail.

## How do you drill through a ceiling joist?

Quote from the video:
Quote from Youtube video: And this one which is a spade bit which is 16 millimeters. So the largest size a hole that can be drilled in the joist is 25 millimeters that's the width of the hole 25 millimeters.

## Can you notch a floor joist for wires?

You can cut a notch at the end of the joist to 1/4 of the joist’s depth (maximum). Along the outer third of a joist, you can cut a notch a maximum of 1/6 the joist depth and 1/3 the joist length without compromising its strength.

## How close can you drill holes in floor joist?

Don’t make any holes with a diameter greater than 1/3 the depth of a joist. ‘ No holes closer than 2 inches to the top or bottom edge. No holes closer than 2 inches to any other hole or notch.

## How much can you notch from a joist?

35mm

Maximum depth of notch of any joist in any situation is 35mm.

## Can you drill through easy joists?

For the engineered I-Joists shown in Fig 1 some of the limitations are: Do not notch or drill holes through the top or bottom ﬂange. It is generally permissible to drill up to 38mm holes anywhere in the web.

## Can I drill a 3 hole in a 2×10 floor joist?

Simply following building code, you’ll only be allowed to bore a 3-5/64″ hole through a 2×10 joist. A 2×10 is actually only 9-1/4″ deep, and building codes set the maximum hole size to 1/3 the depth of the member (9-1/4″ / 3 = 3.08333″).

## How do you fish wire through ceiling joists?

Quote from the video:
Quote from Youtube video: They make drill bits. That are this long and flexible. So what you do is you get to where you need to go and if you have to go over to the next can you'll slide this in bend.