Pulaski

The idea that a building was "finished" and should now be preserved is a relatively new phenomenon, with what are now "listed" historic castles, stately homes, cathedrals and similar buildings being added to, and modified almost continuously, often well into the 20th Century. IIRC a small but substantial tower-like stone entry porch was added in the courtyard of Berkeley Castle as recently as the 1920's (Berkeley castle remains a private home to this day), and I am fairly certain that it would not be allowed today, and I visited Cardiff Castle a couple of years ago, which had been in private ownership until early in the 20th Century, and used as a family home right through the Victorian era, so had been modernized with (IMHO) some truly awful Victorian faux-gothic interiors. Today both these buildings are now permanently frozen "as is" because of the listed buildings laws in the UK.

Lion in Winter

I was slightly encouraged by the stonemason from York's cathedral who worked on the repairs after that fire, but still, nobody has had the chance to do a real assesment yet.

Notre Dame's spire was actually an 18th century restoration, since the medieval one had been deemed unsafe and was dismantled. The restorers then replicated the medieval structure though, using oak.

Pulaski

Was the original spire made of stone? If the oak wasn't even historically accurate it wouldn't surprise me if the new one will have a steel frame.

Lion in Winter

If I understand correctly, it was a combination and that combination was a replica of the medieval construction.

scrubbedexpat142

If not able to go down the traditional timber framing route then Glulam would be miles better than steel. Much better, aesthetically, very strong & better resistance to heat & fire.

scrubbedexpat142

An example of Glulam in a restoration scenario -

Oakvillian

From today's pictures, it seems as though much of the interior of the cathedral was protected by the ceiling vault. The only section of the vaulting that has collapsed is the bit under the nave crossing, which was presumably brought down by the falling spire. The separation of the interior of the building from the roof structure by the vaulted ceiling would also account for the lack of apparent damage to the pulpit, altar and pews at ground level, and probably played a part in the survival of some of the stained glass too.

Finding enough oak of suitable dimensions will be a challenge. Finding masons and carpenters with the skills to effect repairs will be challenging but not insurmountable - there've been enough post-fire reconstruction of historic buildings in recent times that techniques have been rediscovered and re-learned (a fine example being the green oak hammerbeam roof in St George's Hall at Windsor Castle, which was a brand-new design in 1994 rather than a restoration of a previous structure). And in France itself, of course, just 30km or so south of Paris, is the "experimental archaeology" build of Guedelon Castle, which ought to have produced a wealth of knowledge concerning the original construction methods of such a roof structure in Medieval times, and a fair smattering of artisans who now know how to build one.

Octang Frye

Interesting timing. Macron was due to give a speech regarding the Yellow Vest protests.
It's the Reichstag fire 2; Hunchback Boogaloo, I'm telling you. Bring everyone together. Well, I'm not sending a centime. Arrogant Frenchies, always starting wars and invasions and blowing up eco weenies.

I've only ever been in a Catholic cathedral once, for Christmas mass with an ex-girlfriend. It was a lot of fun and I loved the kids singing. Everything being threes.
But what is it with all these icons and relics being ensconced in gold or gold paint material?
It's ostentatious and gaudy, surely totally at odds with what Jesus would have been about? Indiana Jones and the last Crusade got it right with the simple wooden goblet, methinks.

I can't even imagine all the excess at the Vatican. Truly mind boggling.

Pulaski

I am unclear whether the third phrase supports the first phrase or the second.

If you're saying that a structural plywood beam is more resistant to heat and fire than steel then I would appreciate it if you can provide sources for this assertion as it appears implausible at face value and I haven't been able to find any studies that support such a conclusion, and if not, please can you explain how a plywood beam is "better than steel".

Boomhauer

Unless they can get the glulam beams to look like genuine solid timber, it would look out of place owing to its modern appearance. They should do a global search for appropriate timber for the restoration.

Pulaski

But if you look at the pictures, the timber appears to have made a frame to support the roof, and then underneath the timber frame is a vaulted ceiling, so all the timber is entirely out of sight of the people inside the cathedral, like the roof trusses in your home.

Advocating for something that "looks like genuine solid timber" would be pretty much pointless, like suggesting that the roof trusses in your home should be make of high quality hardwoods. Which was why I said that the replacement should be steel, because it is strong, does not require the felling of numerous mature oaks, and is entirely non-combustible.

scrubbedexpat099

Timber of that size and number is very likely unavailable, well not in the sheer volume needed.

5 years to rebuild seems very optimistic.

Boomhauer

Did not know the timber was not visible. Been a long time since I went there, and I was very young at the time.

So, in that case, they could use any material, with preference given to non-combustible lightweight but suitably strong materials

Pulaski

The design of vaulted ceiling under a separate timber-framed pitched roof is common to almost all Norman-gothic cathedrals and churches, there must be hundreds of them in the UK and France, including most cathedrals in the UK - Gloucester, Winchester, Westminster Abbey, Lincoln, Norwich, Durham, Salisbury, Canterbury, Wells, Ely, Peterborough, Oxford, Coventry (the one the Germans bombed), Chester, Chicester, Exeter, etc., etc., and then many dozens of churches …. then the same in France - cathedrals at Chartres, Reims, Tours, Metz, Le Mans, etc., etc.

Here's a picture, showing that some of the vaulted ceiling of Notre Dame has survived even where the timber roof supports above have burned away and/or collapsed.

scrubbedexpat142

The choice of material depends primarily on the loadings. Hardwood has been used for trusses, frequently, when loads & spans are greater than those achievable by softwoods, in all cases timber being preferable to steel.

Steel is great for shopping malls, factories and aircraft hangars.