Long country house floorboard without offset, lay room-long?

I would stick to the usual recommendations and lay the laminate with the main light incidence, so 90° to the window. For the joints, I did it so that every 2nd row is identical. So 1 like 3, 2 like 4, 3 like 5, and so on. It creates a bit more waste but looks good. I like it clearly better than in a random pattern.

And expansion joints are not installed across rooms anyway; an expansion joint belongs under every door.

A floorboard dealer has now told me that a floorboard laid from wall to wall in a row, although I can't do that anymore anyway, would not hold. Just for your information, from the perspective of a floorboard dealer, so that interested parties can better obtain several opinions.

And expansion joints are not installed across rooms anyway, an expansion joint belongs under every door.

Unfortunately false as a general statement. It depends on room sizes and geometries. It would have been better to say that expansion joints of the screed (not a grooving cut, but real expansion joints) have to be included in the laying pattern. However, in buildings with low flow temperature of the underfloor heating, the above statement has already been outdated by practice. At 28-35 degrees flow, nothing expands anymore and "one" lays almost continuously without joints.

The expert might be able to judge that. The layman prefers to install room by room if he doesn't know any better. I also have an expansion joint in the screed between all rooms.

And that nothing expands at 35°C in the supply line, compared to 21°C for example, that would be a physical miracle. Shall we apply for the Nobel Prize with that?

The expert might be able to judge that. The layman prefers to lay floor by room if he doesn’t know better. I also have an expansion joint in the screed between all rooms.

Real expansion joint? That would be more than unusual, trowel cut (fake joint) is more likely.

And that nothing expands at 35°C in the supply line compared to 21°C, for example, that would be a physical miracle. Shall we apply for the Nobel Prize with that?

Then let’s just take the temperature increase in a new building that is properly designed. In the coldest winter it needs, say, 32 degrees supply temperature, so 12 degrees above the summer screed temperature of 20 degrees (that’s easier to calculate). The screed expands at the temperature difference – let’s just assume a 5m room – by a whole 0.7mm. That is negligible. But if you have an old building that runs the underfloor heating with maybe 45 degrees supply temperature, you’re already at 1.5mm ==> then I would definitely transfer the expansion joints (not the trowel cuts). P.S. I actually see hardly any joints in floor coverings at work anymore. Only the really necessary true expansion joints are transferred.