Lost to a devastating fire, the iconic spire of the Notre Dame Cathedral can never be recaptured exactly as it once was ? nor can any other damaged parts of the 856-year-old structure. Built over a period of nearly 200 years beginning in the middle of the 12th century, Notre Dame represents countless hours of skilled labor, and the forests that supplied its massive old growth oak frame are long gone. Felled sometime between 1160 and 1170 and coming from trees thought to be up to 400 years old at the time, these timber beams simply can?t be replaced with trees from today?s forests, which are much younger and smaller.

Preserving the remaining portions of the cathedral will be a challenge, as the Paris fire service has reported that many elements, including the gables that hold the building?s renowned rose windows up, are ?no longer supported by the frame.? A new design will have to find a way to strengthen this frame without the use of old-growth wood.
Architects have noted three main areas of damage, including the hole where the spire once stood, the transept, and the vault of the north transept. To make matters even more complicated, the wooden structures that previously supported the ceiling are waterlogged from efforts to stop the fire, and 210 tons of melted lead from the roof?s shingles poured into the cathedral?s interior, causing additional damage. While most of the stone structure was saved, much of it remains dangerously unstable.

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