Well, I did a trial with a few tiles and then covered them with polyurethane. The trial didn't necessarily go entirely to plan but I was able to establish that PU will be too soft. Epoxy is likely to yellow even indoors, so that leaves me with the following solution: 1. make the tiles thicker (not a big deal) use tile selection and a thicker tile bed to enable a relatively flat surface to be made 3. seal it with a thin polyurethane to protect from mess Thanks for the contributions.

Those holes in the concrete are from the concrete pour. These are not tilt panels as tilt panels are cast lying flat and do not have the holes apart from 1 or 2 from lifting. This concrete is insitu cast. The walls would be formed up with form ply, lvl formwork and the ties. The holes you are talking about are from the formwork ties. As concrete, when wet, is extremly heavy and fluid. The concrete is constantly trying to escape the formwork and get to the ground. The avoid formwork blow outs from the pressure, they use tie rods between the form walls. These rods go through conduit pipes which are in between the formwork. They use the conduit so the tie rods are not encased in concrete making them a permanent fixture. Once the concrete is cured, and the formwork is removed. The tie rods can then be taken out leaving only the conduit. These are then tapped out leaving you with those holes you talk about. If you wish to replicate the look, it will require an engineer, plans and permits and an experienced formworker and concretor. I will attach a photo for further understanding. Scott.

By viable I mean workable, functional. A chimney sweep or a builder adept in chimneys will give you a report. Certainly enquire about a future gas fitting rather than logs if possible. I say this as a fireplace anywhere is delightful and, if downstairs, it could heat upstairs through the house, to a certain point too. If you look at the quality of the brick laying, you will see that its not meant to be a feature which is why it was rendered, but that is choice only. Certainly seal the bricks. Good luck and stay with it if you can. Everybody loves the romance of a fire.

Finished product! Glad I switched the rug the other direction, and the round table kind of plays off the circle window. Truly thankful for all your help! This was fun and I am so happy with the end result. :)