Heated bed movement when heating

Prusa i3, melzi v2 controller

I have noticed how much the heated bed moves/ expands when heating
I put a dial gauge in the centre of my bed, and took the temperature from 20 deg C to 100 the bed move up by 0.41mm with respect to the hot end. and then cooled it back down to 20 deg C where it retracted by 0.4mm .

So a couple of questions is there a way to overcome the movement of the bed height when heating or as the expansion is quite repeatable add some offset in the Gcode for different bed temperatures e.ge PLA v ABS

This is why you should level and zero the bed when it and the extruder are at print temperatures.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Does it move up 0.4mm all around or is it "just" bowing in the middle?
Did you tighten the heatbed down too hard, so it can´t expand freely?
-Olaf