Flitch Plate Holes 1

[jjeng2]

I have an 8" flitch beam that the plumber wants to put a 2-1/2" hole in and several smaller holes. I dont have the hole location plan yet. Are there any references or guidelines or is it even possible to reinforce this with steel plates on the outside. Is there any other standard way of reinforcing holes in a flitch beam? Ive done this many times with steel beams and have standard details and guidelines for hole size, location, and reinforcement. Ive never came across it in a flitch beam.

 

[UcfSE]

A couple of standard rules are no holes in the upper and lower 1/3 of the depth and no holes in areas of high shear. The NDS probably has more information for you. I am not experienced with reinforcing wood flitch beams but I would think that some additional plywood on each side for somuch length might work, provided the numbers work out.

 

[SlideRuleEra]

Here are guidelines for holes in laminated timber beams. I know that your materials are different, but the calcs are based on the same logic and mathematics.

https://www.aitc-glulam.org/shopcart/Pdf/aitc_tn_19_ may_2002.pdf

http://www.SlideRuleEra.net