Hi, I removed the old cloaking fillet from around my bedroom window, and have bought new ones and cut them to size. There is a 1cm gap between the window frame and the wall, as shown in the photos below. Before I removed the old cloaking fillets (the bottom one of which had gone black in places due to mould, and looked horrible), there was no draft, and no sound from outside, but now that there are no cloaking fillets, I can hear traffic much more easily, and there is some air getting in through the gaps. (Nothing terrible, but it will be pretty bad in the winter, I imagine).
Should I fill in the gap with filler before putting the new cloaking fillets on, and what should I use to stick the cloaking fillets on? Do I use silicon sealant, or some 'No nails', or something else? I read on another forum that somebody had had difficulty getting the top fillet to stay in place while the sealant they used dried, so I wanted to make sure I did it properly in the first place.
Many thanks in advance for any help you can give.
(Please click the images below to enlarge them.)