You can use a combination of different secondary heating systems, although from planning perspective the one used to heat the most rooms is technically defined as the 'secondary', (assuming the primary will be heating more than the secondary)
If your look to avoid radiators and taking up spaces on the wall I would suggest underfloor heating, this would be expensive to run, and can take a while to heat a room up but is the least obtrusive,and not overly expensive if using wood or tiled floors.
Other options would include electric room heaters (convection are the most common), and lastly your looking at standard central heating radiators, which could be run from a boiler, heat pump or solar.
Please let me know if you have any follow up questions.
I havent heard back from you in a while, do you still require assistance?
No thats grand thanks
Fantastic, appreciate if you can rate the service received so I may resolve the query.
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