Diagonal holes in framing members?
Diagonal holes in framing members?
(OP)
Do the same 1/3 rules apply for diagonal holes in framing members?
Or do we have to assume the biggest dimension of the hole (5") instead of the diameter (2.5")?
Or do we have to assume the biggest dimension of the hole (5") instead of the diameter (2.5")?

RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
How deep is it? If it's only an inch deep, you might be able to justify it based on the fact that 1x4 let in bracing is a thing.Never mind - I see the pipe size.RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
I'm making a thing: www.thestructuraltoolbox.com
(It's no Kootware and it will probably break but it's alive!)
RE: Diagonal holes in framing members?
Taking the question and assuming that it is valid to assume the length to be considered is only the length on one face (2.5" in your example) and then stretching to apply this assumption to other situations shows that it would become illogical. If you took the same hole and made it nearly parallel to the member, the issue becomes exaggerated. At 5 degrees (as opposed to 30 degrees) the variation between the length on one face and the length through the width of the member. It becomes obvious that assuming the hole can be treated the same as if it went straight through is not an accurate representation. So at the very minimum, you would need to justify that the effect is minimal for certain conditions (e.g. it's ok to assume a 2.5" hole as long as the hole is between 30-90 degrees with respect to the member)
Second argument: Consider the material taken away by cutting the hole. Assuming a 2.5" hole would mean assuming that the additional material taken away by drilling through at an angle is negligible to the analysis.
Again, I'm out of my element here, so take my opinions for what they're worth.
SirPhobos
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
Have I been too long away - isn't the hypotenuse of a 30-60-90 triangle 2X the smallest length? That would make the vertical opening 5 inches, not 2.5 and add 1.7*1.5 to the vertical overlap to be 7.55 inches, at least if the angle is toward the vertical.
If it's more horizontal then the vertical oval is about 3 inches high and the vertical offset nearly 1 inch, so that would be 4 inch vertical overlap.
One could lay the boards side by side with a step the their bottom ends matching the angle over that gap to make up for the offsets to make marking them easier and allow one to bore them before installation.
RE: Diagonal holes in framing members?
Dave, if this a typical job the framer does not cut the holes. Mech trades come in after the fact, and they can be a little crude to get their job done. The worst would try to use an electric chainsaw for this job.
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
But...site conditions are going to make this much worse, so don't run numbers too tight.
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
1) My understanding of non-imperfection related shear failure in wood is that it's primarily about the horizontal shear planes.
2) Following from #1, it seems to me that the parameter of interest is the amount of area lost on a hypothetical, horizontal shear plane.
3) I did a little math on #2 in an attempt to work out an effective hole diameter. Turns out that's just the regular hole diameter. Still, my 8th grade algebra/trig teacher would be proud.
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?
RE: Diagonal holes in framing members?