Superinsulation is an approach to building design, construction, and retrofitting that dramatically reduces heat loss (and gain) by using much higher levels of insulation and airtightness than normal. Superinsulation is one of the ancestors of the passive house approach.
There is no set definition of superinsulation, but superinsulated buildings typically include:
- Very high levels of insulation (typically Rip40 walls and Rip60 roof, corresponding to SI U-values of 0.15 and 0.1 W/(m²·K) respectively)
- Details to ensure insulation continuity where walls meet roofs, foundations, and other walls
- Airtight construction, especially around doors and windows
- a heat recovery ventilation system to provide fresh air
- No large windows facing any particular direction
- Much smaller than conventional heating system, sometimes just a small backup heater
Nisson & Dutt (1985) suggest that a house might be described as “superinsulated” if the cost of space heating is lower than the cost of water heating.
A superinsulated house is intended to reduce heating needs very significantly and may even be heated predominantly by intrinsic heat sources (waste heat generated by appliances and the body heat of the occupants) with very small amounts of backup heat. This has been demonstrated to work even in very cold climates but requires close attention to construction details in addition to the insulation (see IEA Solar Heating & Cooling Implementing Agreement Task 13).