We had our house built 8 years ago and had 2 flues, one up and one down in the basement in case we wanted to have a fireplace in that location in the future. The future is here. Downstairs is a cinder block chimney with a round flue projecting out of it. The cinder block upstairs has an insert. The cinder block upstairs on the main floor is surrounded with concrete stacked stone. We want to do the same thing in the basement. We can surround the cinder block with stacked stone again but the cinder block is completely solid. Does the contractor basically bust a hole through the cinder block in order to install a firebox? Or can we only have a free standing stove with a pipe inserted into the flue which was installed at the time of the house's original construction?