1. Insulating and keeping the entire building private can be extremely expensive in the case of old houses, so separate areas such as bedrooms and living rooms to be insulated and areas not to be insulated.
  2. For windows facing the outside, those that are directly adjacent to a room should be reinforced with insulation using double sashes, and rooms with buffer strips such as verandahs should be reinforced with insulation using shoji (Japanese shoji drums). Install airtight rubber etc. in the gap.
  3. Fill the floor with insulation material to the thickness of the tatami mats, if possible, below the tatami mats, and install a confidential sheet.
  4. Lay insulation material on the ceiling in bedrooms and other areas. Or, depending on your budget, use old futons, old clothing, etc. If possible, install an airtight sheet under the insulation.
  5. Insulate the outer walls of bedrooms, etc. where possible.
  6. A wood stove will be used for heating, and the heat from the smoke exhaust duct will be distributed throughout the space through the atrium.
  7. The area around the wood-burning stove will be finished with teppei stone, a specialty product of the Saku area, which is expected to provide fire prevention and heat storage effects.

additional tips on how to keep warm here from our friend bitsii