Who can I get to insulate below floor and in attic?

Hi,

I want to insulate below the floor boards on the ground floor of a house and top-up the insulation in the attic. Whatever about the attic, I don't think I'd be able to take up floors and put them down again. Are there insulation specialists or what kind of tradesperson would do this work for me? And is it expensive?

Thanks,
g

my brother didthis in my parents house did a great job, almost sound proof as wll as holds the heat, havent a clue how much it would cost to done professionally though! sorry