Hi Maggie, I think it would be best for you to check with the Body Corporate as to what would be allowed.

Thanks Siriuskey - just wondering at this stage if it is technically possible.

yes it's technically possible - if they can get under then they can run the pipes, or possibly only lift a small section of floor to run pipework from above - how about you get a hydronic heating specialist to come and give you a quote / assess your scenario - good luck Cheers PD:)

We had hydronic heating panels retrofitted to a house with a timber floor with minimal crawl space. It is possible and it’s a lovely heat. It would be even better if you can insulate under the floor and draft proof as much as possible. Insulating the walls would be even better again but can be difficult. All the best.

Hydronic radiator panels are probably going to be the most effective option. It should be easy enough to run the pipework under the floor, if there's some space as you say.

Running the pipework externally is probably not the best option if you can help it. Your heat losses will be higher, and the pipe insulation is more likely to degrade while exposed to the elements.