Bathroom extractor fan

We have had mould coming through our ceiling from our loft. We looked into our loft to find out how bad the situation was to find that our bathroom extractor fan is piped into our loft but not connected to anything except the bathroom. This means the bathroom which has a shower in it is venting moisture into the loft itself. Should this have been connected to the outside by the people who built the place? I am in a new build that was built 3 years ago.