No, its not normal. Unfortunately, I don't know where you are in the UK so can't connect this event with any particular weather. Check the plant all over thoroughly for signs of disease, but there's not much you can do now, wait till spring when it starts growing again - it's clearly not dead or it'd have lost foliage from the top as well.

Thank you so much - my location is Hertfordshire. We missed most of the very severe weather but we effected nonetheless. I shall wait till spring and see what happens, maybe a good pruning might do the trick?

Thanks once again

Check for pyracantha scab, through the summer check leaves for dark small blotches in the centre of the leaves, i feed my pyracantha hedge in the s pring with a liqiud comfrey feed which i make on my allotments and it allways looks healthy, but dont worry i have come across pyracanthas on many occaisions which have suffered total leaf loss and have always come back into leaf, clear and burn fallen affected leaves and give it some tlc, if pyracantha scab is the cause then a chemical control may be used instead of the above organic method. julien

Hertfordshire had some very low temperatures and hard frosty conditions at the beginning of winter and on to Christmas - funnily enough, snow is helpful, insulates plants (though it should be brushed off large evergreens) but the hard frosts are much more damaging. Just watch for signs of new growth in Spring, I'm sure it'll be fine.

Thanks for the advice and the reassurance