Joint Ownership Property - How much Tax

My name is on my daughters mortgage (jointly) so she could get a mortgage on a property as her boyfriend had a really poor credit rating - I am also on title deeds ... does this mean i am responsible for capital gains tax on half of the profits when the sale goes through as thsi would be classed as my 2nd home BUT my daughters 1st home

Hi,
Yes. you can. However, you need to submit a declaration of trust showing that you have no beneficial interest in the property so that you are not liable for any gain if or when the  property is sold.
Thank you.