Hello all, I would appreciate some help on how to route the microbore
for the two new rads in the extension. the pipes need to go through the
joists, so is it a case of drilling or notching?
Notching would be the easiest way to run the pipe but I want to do it
correctly.

Also could you please confirm from what i have read in the building
regs regards drilling holes in joists. holes to be drilled in a zone
from .25 - .40 X lenght of joist and holes to be spaced 3X diameter of
hole apart. and no more than 1/6 diameter of width of joist.

many thanks once again.