Lawn Renovation

Hi all,

I am renovating my lawn and have a question about the best way to proceed.

I have killed off my lawn, and have raked some of the dead grass, however, i now have a very thick root bed and soil which I cannot even press more than 1cm into.

Do I need to hire a scarifier?

I’ve been manually forking and flipping but this leaves some of the roots in.

thanks.