Hello Ayrton Windows here...Velux are specialist roof light windows so not something we would be able to help with - however take a look at their website http://www.velux.co.uk/Private/Service for tips on repair or contact this specialist Velux company http://www.roofwindowrepair.co.uk/
For beautiful replacement sash and casement windows contact us!! good luck

Please post your answers as I need an answer to this too :-)

One of our velux windows has started to leak when it rains. On inspection we've noticed the seal has torn. Does anyone know who to contact for a repair? Any recommendations?