The maximum allowable diameter of a hole in any solid lumber joist is one third of.
Drilling holes plumbing through floor joists.
But the pipe will be above floor level or thereabouts especially if you use a shallow trap.
Engineered floor joists can be drilled only according to their manufacturer s guidelines the code specifies the maximum size of the holes you can drill or the notches you can cut where you can and can t place them and how far apart they can be spaced.
I hate putting waste pipe through joists for the reasons.
There are very specific locations and sizes in the code telling you what is allowed.
Drilling floor joists to run plumbing wiring or ducts can be tricky.
I noticed that quite a few people have a common concern that drilling holes in joists will make them weaker.
Even if you are going to drill a hole through the joist one of the problems you are going to get is threading the pipe through and you don t want any joints in the ceiling space.
Use our joist notch and hole calculator to ensure that you get them in the right place in your joists.
I m here to let you know that you can safely drill holes in joists by following a few simple guidelines.
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.
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.
Keep the hole at least 2 in.
But modern living requires electrical wiring and plumbing.
Where and how to drill joists for electrical cables or plumbing runs depends on what type of floor framing you have.
Drilling holes in joists for plumbing and pipes is easy and we show you how in this video.
Notches in the top or bottom of joists shall not exceed one sixth the depth and shall not be located in the middle third of the span.
You often require drilling holes in ceiling joists to pass any electrical or plumbing runs through the ceiling or floor.
From the top and the bottom if it s a dimensional lumber joist.
There are regulations in the uk you must follow in new build insta.
How to drill a hole through the side of a floor joist.
Lean how to notch a joist for pipes and cables if you need to run pipes or cables under a floor.