What you're writing means that if I want to reinforce with glued screw plywood, I might as well place a 200x200 piece on each side of the opening, just to ensure that the entire beam doesn't crack along the grain in the middle of the beam....
That there's basically no other weakening that's particularly severe.
Yes, in principle, as long as you are at a good distance from the stockpile. The reason for choosing plyfa is that it is strong and does not take up much space.
Feedback.
Here's how it turned out. The holes didn't end up in the middle of the beams, but relatively high. But it might actually be better, since I'm going to screw-glue 22mm floorboards which will become part of and contribute to the construction. So the holes will probably be quite close to the neutral plane anyway.
Oh right, then there will be 12-25mm of levelling compound with 2.5mm mesh too, on the boards, which should also contribute to the strength.
Can you tell I've had some anxiety over this? But I'm starting to feel more and more that I can sleep well now.
I have screw-glued and clamped with 12mm plywood pbs. It's not construction plywood!
And the beams were a bit warped, which made it difficult to get it perfect. It might not be perfect.
But hopefully the plywood helps a little, strengthening both the moment of inertia a bit and preventing splitting a bit.
But I'm starting to feel more and more that I can sleep well now.
