Legal problem with my new carpet?

i have recently had a stair carpet fitted and now have the grippers sticking through to which have hurt my childrens feet, i have contacted my fitter, he said the carpet supplied to me was unsuitable for stairs even though i told the supplier what i wanted the carpet for. Does the carpet seller have a duty and responsibility to properly advise me, and am i entitled to new carpet e.t.c or is it just tough luck?? where do I stand legally??