Own work in new construction - what makes sense and is feasible?

If you really want to, you can do almost everything yourself. All internal insulation work (roof, underfloor heating), laying underfloor heating (many heating engineers do this because you can’t really go wrong with endless installation), walls and floors, chasing for the electrician, outdoor facilities (as long as no heavy equipment is needed), fine assembly of sanitary installations.

These are all things that someone who doesn’t have two left hands can do very well themselves. Even large-format tiles are quite manageable for a layperson with the means available today.

But the easiest way to save costs is always not to produce any costs.

We have spent almost a year reading up, watching videos, and are building our house together with a master foreman from our house company. He stays with us for 10 days and shows us a lot. If we need him, he will come again (of course for money ;)). We also have an expert.

We do the drywall ourselves, insulate ourselves, lay the floors ourselves (tiles and wooden planks), and also do the wall cladding (mostly wood paneling inside, partly to avoid sanding :D) ourselves.
For the outdoor facilities, we only have the substructure for the gravel-flower-lawn for the driveway done by others, and we do the rest ourselves.

So far, we have experienced that no one puts in as much effort as we do ourselves. We have no pressure to move out, as we have shared flat rooms and a very cheap apartment. There are no children to take care of either. Everything that could cause the house to explode or flood (heating, sanitary, electricity) we have done by professionals. We will also have the main bathroom tiled to avoid any mishaps (if we find someone for such a small job).

Maybe we are totally overestimating ourselves, but we are (still) optimistic, even after our first fail, applying the bitumen sealing membrane on the floor slab (time management and such).

But we don’t have to have everything perfect, we don’t have 150 m², no left hands, and a lot of fun in handiwork.