roof replacement vs new roof

https://wiki-wire.win/index.php/What_a_Builder-Grade_Roof_Means_for_Your_Austin_Home

Deciding between a roof replacement and a new roof comes down to the structure underneath. A replacement usually means tearing off old shingles and putting down new ones, while a new roof is for a house under construction or an addition. Your roofer can inspect the decking—if it's rotten, you might need a full tear-off, not just an overlay.