ᐅ What type of heating system (including domestic hot water) would be suitable for a tiny house?

Hello everyone. I am planning to build a tiny house in my garden (2500 m² (26,910 sq ft)) with approximately 20 m² (215 sq ft) of living space, as a backup for adult children and other visitors since we live in a small bungalow ourselves. It will be almost fully equipped. All necessary connections will be available. The walls, foundation slab, and roof structure have a U-value of 0.18 W/(m²·K) (0.03 BTU/(ft²·°F)), which results in a heating load of 1.4 kW.

Instant water heaters and fan heaters for heating, or as a luxury option, IR panels. If heating is required continuously or frequently, you might want to consider a split air conditioning system.

Fan heater or an air conditioning unit.

Split air conditioning or the quick and dirty US version in the window (window air conditioner)

Alternatively, a small wood stove or a makeshift gas heater from a camper.

In principle, a stove would also work. However, an electric heater is more practical for automatically keeping the house frost-free.

I tend to agree with @boxandroof on using tankless water heaters and infrared panels with a simple plug-in thermostat. They are maintenance-free, cost-effective to install, and suitable for occasional use.