This seems to simulate the pressure due to the weight of the bricks, but I wonder how much the height comes down by if you factor in the extra pressure you have

This seems to simulate the pressure due to the weight of the bricks, but I wonder how much the height comes down by if you factor in the extra pressure you have to put on the top brick to get it to clip on. Does this add non-negligibly to the pressure on the bottom brick, or is it almost nothing once dispersed through the whole tower? (You may be able to tell that I have very little knowledge of the physical sciences, so apologies if this is a stupid question!)