There is at least one room in the upcoming Resident Evil HD Remake that was entirely remade, but producer Yoshiaki Hirabayashi explains why this wasn't done throughout.
You can check out the video that showcases the possibly only entirely remade room below, which is also pictured above. The opportunity to create better and more consistent lighting from the flame is what prompted this particular room to be remade. Hirabayashi also explains why the whole game wasn't remade: to do so had the potential to remove the game's difficult to quantify soul.
For more from Hirabayashi, you can check out part one of the video series (above is part two) by heading here. You can also find a pair of interviews with Hirabayash care of Game Informer's resident Resident Evil expert Tim Turi by heading here and here.
[Source: Capcom Unity]