Running pipe INSIDE floorboard?

[phloaw]

I need to run central heating pipe horizontally under the floorboards of an upper floor. I need to go through only one 75mm wide beam, but I'm wary of boring or notching it, also because that would be quite close to the wall bearing the beam.
So I thought of running an 8mm or 10mm pipe immediately over the beam, by digging a ditch on the lower face of the 18mm floorboard resting on the beam, to accommodate the pipe.
I wanted to know if this makes sense, and how to prevent possible problems such as noises and pipe wear (on the long run). Also: plastic or copper pipe?
Thanks!

 

[JG plumbing]

Draw a sketch of what your thinking of doing. I don't know what you mean by digging a ditch.

 

[FishScreener]

The depth of beams and joist is governed by the depth neede to handle the moment load in the middle of the span, and stay within allowable deflection. You can generally cut a notch close to the end, where the beam is in shear, with no issue.