I don't want to sound rude(I really really don't want to) but actually 20K in a house fire is less. I consider you as lucky......
The main house structure is insured I guess. The worst thing is the other stuff which isdestroyed. Like a TV, DVD player, Fridge, Microwave, computer(alone would usuallyt be more than 30K), etc.....
So, you should consider yourself lucky that first and foremost your whole family escaped without injuries(at least that is what I hhave gathered) and secondly the damage is only(???) 20K.