We’re planning a major renovation of our bungalow (full exterior being replaced and interior gut).

While doing an energy audit we discovered we have basically a whole other house in our attic.

We wouldn’t use this as living space in the short term but the current cost of housing I could see our kids staying with us well into adulthood.

With the current gut of the house planned, would you make access to this space, do the engineering, and get hvac/water/power to make it useable?

I know we have rafters not trusses and live in Ontario where we get summer and winter. House is about 20 years old.