Urgent project led by Louis that Carl prioritizes over sealing the breached safe room door.
When Rosetta presses for a decision on isolating or killing the Doggie Door, Carl agrees the safe room must be separated but tells her the conversation has to wait: for the next few minutes, everyone should focus on helping Louis open the roof.
His reasoning is blunt — none of the safe room planning matters if they don't beat these assholes back first, and the enemy main force is only ten or fifteen minutes out with armor, numbers, orcs and reportedly Prince Stalwart leading. The roof work therefore takes precedence over every other engineering task in camp.
The defense's most urgent engineering priority in the gap between assaults.