Caulking panel grooves?

[Yrrol]

When it's impossible to hammer the fascia board back and you're left with a gap between the bottom board and the fascia board... Is it worth caulking then? I find all caulk tends to crack over time.

I have a few boards that are starting to become bow-shaped and can't be forced back against the bottom boards, but I think it's probably better to replace them completely than to caulk.
- But maybe I used the wrong caulk, or not enough caulk, when I've experienced it cracking and leaving a gap again.

 

[Marcussjogren]

It will probably hold for a while, but sooner or later the joint will crack and that sucks.

Can't you drive in extra nails to secure the trim board properly and then putty over the nail head? It's not very pretty, but a much more durable solution.

 

[Marcussjogren]

It's also insanely ugly with latex sealant on wood paneling, the previous owner of our house, for example, liked to patch with fox when he had cut crooked.