In order to make the concentric inner wall iin the picture, I had to duplicate the outer wall and then manually butcher the polygons it until it was what I wanted. I wanted to make a large structure with around 50 such concentric walls and so it's going to take forever.
Unforunately just scaling the duplicate obviously scales the size of the 'bricks' as well.
Can anyone suggest a shortcut to do this?

Thanks

Steve

(FWIW, the original wall was made with a subdivided poly cube with the the inner sections deleted. Then a duplicate was made and edited to provide the inner walls to give the appearance of it being solid.)