ᐅ Long, wide-plank flooring without staggered joints, installed lengthwise along the room?

I would follow the usual recommendations and install the laminate flooring perpendicular to the main light source, so at a 90° angle to the window.

For the joints, I arranged every second row identically. So row 1 matches row 3, row 2 matches row 4, row 3 matches row 5, and so on.

This creates a bit more waste but looks good. I definitely prefer it over a random pattern.

And installation across rooms is not done anyway; an expansion joint belongs under every door.

A flooring dealer recently told me that installing a plank continuously from wall to wall would not be stable, even though I can’t do that anymore anyway. Just for your information, from the perspective of a flooring dealer, so that others interested can gather several opinions on this.

xMisterDx schrieb:

And expansion joints are not installed across rooms anyway; there should be an expansion gap under every door.

As a general statement, this is unfortunately incorrect. It depends on the room sizes and geometries. It would have been better to say that expansion joints in the screed (not surface cuts with a trowel, but actual expansion joints) need to be integrated into the installation pattern. However, in buildings with low supply temperatures for underfloor heating, the above statement has already been outdated by practical experience. At 28-35°C (82-95°F) supply temperature, there is hardly any expansion, and the flooring is often installed almost continuously without joints.

A professional might be able to assess that. An amateur usually prefers to install room by room if they are unsure. I also have an expansion joint in the screed between all rooms.

And the idea that nothing expands at 35°C (95°F) in the supply line compared to 21°C (70°F), for example, would be a physical miracle. Should we apply for a Nobel Prize with that?

xMisterDx schrieb:

A professional might be able to assess that. A layperson would rather install by room if they don’t know any better. I also have an expansion joint between every room in the screed.

A real expansion joint? That would be more than unusual; a trowel cut (dummy joint) is more likely.

xMisterDx schrieb:

And that nothing expands at 35°C (95°F) in the supply line, compared to 21°C (70°F) for example, would be a physical miracle. Shall we apply for a Nobel Prize with that?

Let’s just take the temperature increase in a newly built house that is reasonably designed. In the coldest winter, the supply temperature might be 32°C (90°F), so 12°C (21.6°F) above the summer screed temperature of 20°C (68°F) (this makes the calculation easier). The screed in a 5m (16.4 ft) room would expand by about 0.7mm (0.03 inches). That is negligible.
However, if you have an older building where the underfloor heating runs at maybe 45°C (113°F) supply temperature, the expansion would already be around 1.5mm (0.06 inches) — in that case, I would definitely keep the expansion joints (not the trowel cuts).

P.S. In my work, I hardly see floor joints anymore. Only the absolutely necessary real expansion joints are preserved.