Ain't that the truth! Thanks for taking the time to share your thoughts, Tora! Really great questions/ideas for me going forward and I'm sure others will benefit from them as well. Learning from someone who has gone through something similar can help each of us find the best balance regarding cost/time/materials for our projects.two minds are better than mine
This is our second winter in the house and most of the projects that had to be completed are done, so now it's time to work on improving quality of life issues. I'm also the type to fixate on a project, so at the moment it's insulation and heat loss. Sorry for hijacking the post!
One area that I've had to reorient my thinking on is that our first and second floor are not connected. We essentially have two separate units. In every other house I've lived in, both in America and Japan, the second floor sits on top of the first. But with this house, there is a large gap between the 1st floor ceiling and 2nd floor floor that is open to outside air. There are also large areas of dead space above the 1st floor ceiling, meaning the 2nd floor walls, while under the roof, have to be treated as essentially exterior walls for insulation purposes. You can see this in the attached picture. Most of that insulation looks ok, but some needs to be replaced. Also, the closet walls are not insulated. I would like to do that.
Regarding doubling up 50mm insulation: I've read some stuff that says if it's 'faced' insulation you shouldn't put it over existing insulation. The 'face' could trap moisture. This is the insulation I have. What say all? Should the insulation be 'unfaced' before laying it over the existing insulation?
I'll stop there for now.