how high do the fill em up mate ?

wanna ripp em out but bricks are heavy as i live on the first floor,,,,, that lot is just the bricks that was covering the other bricks to make it tidy,,, and that was 4 ikea bags full to take out aswell as the actual fireplace and the 2 concrete blocks for the hearth and base thingy


why do they fill the gaps then ?

is it all the way to the top then ?