Hi there, Just starting to decorate my house. It is about 9 years old and hasn't been decorated from new. There are a few cracks near the windows and doors in a couple of places. I presume these are settling cracks as they are less than 5mm. Just wondered what the best way of filling these gaps? Do I use something like polyfilla or do I need to use something that is flexible. Any help would be much appreciated as I am new to all this. Thanks