I have a carpet shop in Fife, and we've fitted quite a few stairs with runners. The runner doesn't need to be in one piece, it could be cut into strips from the 4m width and joined behind the stair rods. Even if you don't want stair rods (which are purely decorative by the way!) the carpet can still be joined there. Crucial Trading should be able to advise you of a trusted retailer in your area who can measure up and advise you on the best solution for your landing too! Hope that helps, good luck!

Since you asked about runners OR wall to wall carpet, I thought I would show you something we did to accommodate my husband's desire for carpeted stairs (less slippery), neither of us really wanting a runner, and my dislike of vacuuming risers. Not the best pic since this was taken more to show a couple places they needed to touch up paint, and is a close up of our basement stairs but here you go. I am really pleased with how they turned out, and it ties the flooring on our main floor and upper floor together well. You could of course also do this with a fancier patterned/coloured carpet :)

If you have a stair runner going up the centre of your staircase, what happens on the top step going onto your landing? Do you have to have floor boards and the same runner carpet with a gap boarder around in front of all the bedroom doors? Can you have normal bedroom carpet fitted as a runner (so that it can blend into full carpet on landing? Or is that not possible/weird? I just don't understand lol Someone please explain, pref with photos please :-)

I have sisal flooring in my garden room. We previously had seagrass down. The first lot got wet. Nightmare. It marked. We only went for the similar flooring because the leak was sealed otherwise I would not have chanced it. I don’t think any of the natural flooring reacts well to wet or dirt.