Brian in MA wrote:
The oak trees were 300-400 years old when cut down for the beams. Don't know where you would find those kind of trees in that quantity. ^^This. I read earlier that the wood for the beams came from primal forests when it was originally built and that trees that size are no longer available to be cut.
I would think also with current fire codes that they would have to use other materials. The town next to where I live had a huge wooden church (the steeple height was close to 200 ft) dating back to the 1830s that was struck by lightning last year and burned to the ground. Same issue where the local fire chief said older structures like that are tinderboxes waiting to happen, and that when the new structure is built will have to be up to code.
This is from a manufacturing perspective. In France, wood use is rather popular method. About 5 years ago, we added ~40k sq ft addition on to a facility. The trusses and main center beam were laminated wood. For a logistics building, it was quite unique compared to what you would see in the US and looked fantastic.
The restoration project will certainly take a while. I would assume it will be back under roof with in 2 years. The rest of the restoration can then start after that. I would guess total time will be above 5 years but under 10. If you have never been to Notre Dame, it is hard to see in pictures how large of a building it actually is.