Or do you mean that the surface on all of the wall are changing, not just one of the walls.
That is because you have them all selected.
If you want to change just one, then just select one.
If you want to change many, then you select many.
What you have selected is what will be changed.
With the exception of when you have walls and slabs selected at the same time (i.e. different elements).
You will only be changing the properties of one element type - not all of them.
But all selected elements of that type will change.
Look at the info box and you will see the properties for only one of the selected elements.
It is those elements that you will be changing.
You have to select different element types separately to change them.
Barry.
One of the forum moderators.
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