There's no need to replace your skirting .
Just fill the gap with decorators caulk allow
to dry then paint over.
If it is a large gap then fill it with some newspaper
and then run over with the caulk.
This will give the caulk something to sit on and save you
time as you will not need to go over it many times
You can buy this product in B&Q , Asda and
any hardware store and it only costs a few pounds.