Stair carpets

[yuccaman]

I have just had a Berber carpet 'professionally' fitted. I use 'quotes' as being that the weave lies different ways on different stairs, I'm not sure of the professionalism!

Anyway, should the carpet be loose on the stairs at all (there is a good 1-2" play on each stair) or should it be tight? The vertical bit of each stair is best described as baggy. To me, this seems dangerous!

Help..?!?!...