I’m curious to hear about what you did with the house (I’m thinking about building/renovating a house in a few years). Did you go DIY or hire a contractor? What were some of your replacements for plastics?
A note on the contractor question: The basic construction of the house is quite simple (post and beam not too dissimilar to the German "Fachwerk") and given the right tools and location could be done completely DIY. Check out this YouTube channel for traditional wood framing techniques: https://www.youtube.com/@KrisHarbour Our contractors used a more modern design approach and metal fasteners but it is basically the same basic construction.
Professional contractors have professional equipment for this type of construction, though and can put it together really quickly. The basic framing of the house was constructed over a couple of months or so off site (with mostly two guys being involved, I think), transported in pieces to the build site and put together over the span of five days, including the roof construction. The insulation and OSB were added over the span of a few weeks.
We basically built an all-wooden house: Timber posts and beams (not the flimsy sticks that are used commonly in construction in the US but solid 8" posts), interlocking OSB-boards on the inside for air tightness (this can also be achieved with other wood-based techniques, my house has an air tightness comparable to passive house construction), wood fibre insulation material (15+ inches on all sides and the roof), clay plastering on the inside (great for thermal mass).
The house is really air tight but moisture can get out through the walls easily without causing rot. There are thermal bridges. Window frames are from oak. We have a bit of plastics-based insulation around the foundation and the roof is covered with an oil-based-rubber, but that's about it except for smaller items like cable insulations, switches, etc.
We did some of the interior stuff DIY but the major parts of the construction were done by various contractors.
We chose wood fibre because we wanted the house's CO2 footprint to be as low as possible. We are slightly above passive house levels in terms of ongoing energy use (mostly because the house has an inefficient shape = not a cube) and we produce more kw/h from solar power each year than we use despite having a relatively inefficient electricity-based heating system. But we also wanted to reduce the CO2 emitted during construction and cement/concrete is really bad in that regard.
The wood fibre insulation has a fraction of the embodied energy/CO2 emissions of concrete and fossil fuel based insulation and it is fully compostable. I could theoretically also be reused if the house is demolished at some point, as it doesn't deteriorate if it stays dry (or is allowed to dry quickly after getting wet), though I think that would be unlikely to happen. Also, wood fibre is an excellent insulator against heat, which is nice given that our summers can get quite hot.
The wood-only construction also eliminates all thermal bridges, as wood is itself an insulator and the required fasteners are small diameter and do not reach through the entire wall.
Professional contractors have professional equipment for this type of construction, though and can put it together really quickly. The basic framing of the house was constructed over a couple of months or so off site (with mostly two guys being involved, I think), transported in pieces to the build site and put together over the span of five days, including the roof construction. The insulation and OSB were added over the span of a few weeks.