Daylight showing between slates in roof that has just been relaid

It is normal to see what you describe on an unfelted roof but wondering how you can even see the slates if the roof has been refelted.

Hi you should not see daylight between the slate gaps, each slate laid should cover the corresponding gap thus keeping it water tight, in fact a correctly slated roof should be water tight without even having felt. However due to the new breathable felts being opaque to light it can often seem you have loads of gaps, where as in reality its not as bad as it looks. I would advise calling out another roofing contractor in your area to access and take a look, this should be free of charge. Hope this helps, South Coast Building Solutions Ltd