Cutting wood for the roof frame yourself - Moisture - Schedule

I am missing a large amount of information here to even assess whether the gable roof as a rafter roof made from beams cut as fillets from the grown trunk is actually the smartest way. Isn't this already very outdated in terms of time, construction technology, and market to afford this luxury (what is it supposed to be good for?) just because you get the raw material at purchase price?

Because it can crack, shrink and warp brutally. Our wood was stored as a log for three years, then sawn and dried further in the drying chamber. Which was not cheap either. The carpentry shops do not use wood stored in Schierschandudel or glued laminated timber beams.

So he still wants to make the purlins out of glued laminated timber beams. But nowadays no one has time to dry the trees for 3 years, right? I suppose the wood is delivered and processed immediately, isn't it?

You cannot use freshly cut wood for construction. Depending on the type, wood has 60-65% moisture content, which is dried down to about 20% moisture content for construction wood. This takes time and leads to shrinkage. If wet wood is forced firmly into shape by constructions, it will crack. The process can be accelerated to a few weeks in drying chambers, but naturally dried wood should be left for 2 years or longer.

Can you exchange dry wood for fresh wood with the carpenter/sawmill

Why would that be a no-go for you? I think the company has executed most of their built roof trusses that way.

Then he doesn’t understand his business ;). You can just google experiences with damp wood in roof trusses. From endless mold to cracks, shrinkage, and so on. I don't want that in my house. Besides, ask your carpenter what installation moisture the DIN standard suggests and why he wants to deviate from it. Damp wood is NOT state of the art and a serious defect.

But nowadays nobody has time to dry the trees for 3 years, right? The wood is delivered and immediately processed, I guess, isn’t it?

Don’t guess ;) . Damp wood is not processed (and must not be). Damp wood is dried. Either started drying three years ago or, very modern, "kiln-dried". That is as normal as breathing.

I am missing a lot of information here to even judge whether the saddle roof as a rafter roof cut from beams as fillets from the grown trunk is actually the smartest way. Isn’t this already very outdated in terms of time, construction technology and market, to afford this luxury (what is it good for?) just because you get the raw material at the purchase price?

What else should the beams be made from, if not from a grown trunk. As mentioned, the purlins are made from glued laminated timber beams. Well, the wood prices are still at a very high level.