Should You Drill Floor Joists

How to position holes correctly so they don t weaken the joist.

Should you drill floor joists. You can t notch or drill them anywhere. How to drill through floor joists. B the guidelines are simple. No greater diameter than 0 25 times the depth of.

Measure up 2 inches from the bottom edge of the joist and mark it again. Mark the joist at that spot with a pencil. Irc r502 8 and irc r802 7. For this discussion we will focus on the traditional dimensional floor joists.

Cutting notches and drilling holes in joists. If you re remodeling or building with i joists your lumber supplier can provide you with a set of hole drilling standards to follow. You can safely drill joists for electrical and plumbing runs without weakening the joists if you follow the rules. First let s take a look at the code 2012 international residential code to see what is required when drilling floor joists.

As part of any new installation work or a re wire a cable trunking or cable tray sometimes has to pass through an element of building construction such as a floor wall or beam necessitating the formation of a notch or opening in the element. For those working with the less common open web or floor truss joists fig. Guide to making safe cuts holes and notches in floor joists and ceiling joists. The rules for positioning notches in floor joists image courtesy of niceic to understand the forces at work in a joist particularly the tension and compression forces please see our project that explains how the forces that affect buildings work.

The guidelines for these are shown in fig. Rules for holes in joists. Measure down 2 inches from the top edge of the joist.