Bolting through the neutral axis will have negligible effect on the
stiffness of the beam
A 12 mm hole is about an eighth of your depth, Stiffness proportional to
depth cubed, so about 0.2% reduction..
There is no need to glue the beams together (as confirmed by my structural
engineer)


"Steve" wrote in message
.uk...
Steve wrote:

One idea was to double the joists up i.e. putting extra joists in between
but in the areas of high load to have double joists joined, but I had
thought of glueing them together and bolting through the neutral access.
Any problems with glueing and bolting?

I'm sorry but access was not what I meant to type!

Neutral axis