Notre-Dame on fire, apparently...

[pcolbeck]

My nephew  and his colleagues at Salisbury Cathedral may be some of the experts seconded for the rebuilding.  There's an international shortage of qualified and experienced cathedral stonemasons.

My father inlaw is a cathedral stonemason. York Minster, St Georges Chapel Windsor and several others. Ended up in charge of maintenance for Ancient Monuments for the North of England. Maybe they will offer him pots of cash to come out of retirement.

[Aunt Maud]

I had a look at the section on the roof on Notre Dame website    http://www.notredamedeparis.fr/en/la-cathedrale/architecture/la-charpente/

Then I thought about what I had read about there not being enough oak around to rebuild the roof frame. I think this is just the opinion of a few "experts" on medieval architecture having a mild panic attack.

The pictures below show the quality of oak available at the moment in a single woodland near where I live. The stems are up to 11m long and 400mm - 600mm in diameter at their mid point.

These stems, although impressive, are not the largest in this woodland by a long chalk, there are 36 trees with a diameter of 1m in there. Neither is this woodland unusual for this part of Europe and I can name at least 4 woodlands within 50km of here which have similar standing oak trees.

The ones with a V on don't exist any more, as I have chopped them all up for joinery in my house. 

[spesh]

There might be enough timber that's the right size, but a key question is how well-seasoned would it need to be before it can be used for rebuilding Notre-Dame - you mentioned weight up-thread, but I'd have thought that shrinkage/warping might also be an issue.

[Exit Stage Left]

Quite a lot of 'shake' in those trees.

Work on shake by the Forestry Commission has stressed that to avoid it oak should not be grown on dry, stony and gravelly soils, and damage to trees should be avoided in harvesting. These can act as 'triggers' for shake.

http://www.futuretrees.org/our-work/oak/shake-in-oak/

[Aunt Maud]

The splits just from the ends being in the wind, if you go down to any wood yard you'll see that.

As for building with, this stuff is traditionally built with whilst it's green as seasoning it would take an age and make it difficult to work.

[spesh]

The splits just from the ends being in the wind, if you go down to any wood yard you'll see that.

As for building with, this stuff is traditionally built with whilst it's green as seasoning it would take an age and make it difficult to work.

OK, fair enough.

[Regulator]

My nephew  and his colleagues at Salisbury Cathedral may be some of the experts seconded for the rebuilding.  There's an international shortage of qualified and experienced cathedral stonemasons.

My father inlaw is a cathedral stonemason. York Minster, St Georges Chapel Windsor and several others. Ended up in charge of maintenance for Ancient Monuments for the North of England. Maybe they will offer him pots of cash to come out of retirement.

I wouldn’t be surprised...  my nephew has only been qualified for a couple of years and has already had offers from other cathedrals- both in the U.K. and overseas.

[Aunt Maud]

The splits just from the ends being in the wind, if you go down to any wood yard you'll see that.

As for building with, this stuff is traditionally built with whilst it's green as seasoning it would take an age and make it difficult to work.

OK, fair enough.

Which is why I mentioned the weight, as a new one would be at least twice as heavy as the one which was there on Saturday.

[Jaded]

My stonemason served 10 years on a cathedral. Wonderful craftsman. Not sure he’ll want to go to France though.

[Exit Stage Left]

The splits just from the ends being in the wind, if you go down to any wood yard you'll see that.

Maybe, maybe not.

The term 'shake' describes the longitudinal separations in the wood of standing oak (and sweet chestnut) trees that can severely reduce the conversion potential of stems. They occur either radially (star shake), or around the circumference of an annual ring (ring shake). The separations, if not already large, tend to extend during timber processing. Shake has been recognized as a serious problem to users of oak since at least the time of John Evelyn in 1664. It occurs in nearly all British and Irish oak plantations and quite often affects more than 50% of the trees in a stand. The roadside value of shaken timber may be as little as 20% of that of sound timber. It has been estimated that an average of a little over 20% of all oaks in Great Britain may be shaken though there are regional variations. A consequence of this is that the Timber Trade has low expectations of oak, which are reflected in low prices.

It's why merchants are reluctant to buy standing Oak and Sweet Chestnut.

[Aunt Maud]

Maybe, maybe not.

The term 'shake' describes the longitudinal separations in the wood of standing oak (and sweet chestnut) trees that can severely reduce the conversion potential of stems. They occur either radially (star shake), or around the circumference of an annual ring (ring shake). The separations, if not already large, tend to extend during timber processing. Shake has been recognized as a serious problem to users of oak since at least the time of John Evelyn in 1664. It occurs in nearly all British and Irish oak plantations and quite often affects more than 50% of the trees in a stand. The roadside value of shaken timber may be as little as 20% of that of sound timber. It has been estimated that an average of a little over 20% of all oaks in Great Britain may be shaken though there are regional variations. A consequence of this is that the Timber Trade has low expectations of oak, which are reflected in low prices.

It's why merchants are reluctant to buy standing Oak and Sweet Chestnut.

This is prime wainscot oak from the Baltic and has been prized by joiners for its figure and straight grain throughout history. Which is why this kind of oak oak goes for £190+vat per cubic foot at the merchants and has always been used for the best joinery.

It's not the kind of timber you would stick up in a roof because its clear and the quality is too high. I posted pictures of it to show the size of trees available at the moment and just because you don't like the look of it, doesn't mean its shit.

You cut the oak for the purpose which it is suitable, any fool knows that.

What do you know anyway about using this kind of timber anyway, you only cut hedges.

And by the way, they aren't standing trees because they're laying on the fucking ground. Arse!

[Exit Stage Left]

That looks like the sort of acidic heathland soil that can give rise to shake in Oak. If you are looking for beam-quality timber you'll tend to be looking at brown-earth sites where the incidence is lower. You can then buy standing timber with more confidence.

Timber is sold standing by preference.

We normally recommend standing sale by competitive tender as being the best method of selling timber. This aims to maximise income and minimise risk for the owner. Alternatively timber can be sold by negotiation, private treaty or auction.

http://www.hwforestry.co.uk/timber-sales

Even second quality graded beams specify no shake, for obvious reasons.

QP1 Grading (Second highest quality)

Sawn timber with practically sharp arrises, permitting wane less than 10% of the face width across no more than 30% of the length.
This width tolerance is increased to 15% for sections above 250 x 250mm.
Sound sapwood permitted on two arrises if the total width is less than 15% of the face width.
Fully or partly intergrown sound knots are permitted if the diameter is less than half the face width.
Boxed heart permitted, as well as traces of heartwood on both faces. Slope of the grain less than 12%, not exceeding 20% locally.
Permitted on a limited number of pieces: brown streak, black holes, brown pith. Excluded: unsound knots, frost crack, ring shake, star shake, curly grain, bark pocket, unsound sapwood, rot, white holes.

https://www.iwood.co.uk/timber-knowledge-library/timber-construction/beam-grading-rules---qpa-and-qp1/

I'm no joiner, although both my father and grandfather were time-served. I'm more interested in forestry. As I mentioned upthread, my partner manages one of the woods which provided oak for the York Minster restoration, so this sort of thing gets discussed at home.

Heather had a visit to Fontainbleau a while ago, where there's a big National Forest, and that's where the timber is likely to come from, and the state will be bearing the risks of sub-grade stems. As mentioned upthread there's still a lot of timber around from 1999.
https://en.wikipedia.org/wiki/Forest_of_Fontainebleau

[pcolbeck]

One of the other French cathedrals rebuilt their roof after a fire using reinforced concrete beams moulded to look exactly like wooden ones down to moulding the wood joints. This was specifically to reduce the fire risk. I wonder if they will do the same thing with Notre-Dame? The Sagrada Família in Barcelona uses moulded concrete for its mad vaulted roof as well.

[Exit Stage Left]

One of the other French cathedrals rebuilt their roof after a fire using reinforced concrete beams moulded to look exactly like wooden ones down to moulding the wood joints. This was specifically to reduce the fire risk. I wonder if they will do the same thing with Notre-Dame? The Sagrada Família in Barcelona uses moulded concrete for its mad vaulted roof as well.

Reims, I mentioned that on page 1, when Notre Dame was still on fire.

[pcolbeck]

Yes thats the one I was thinking about. I visited it last year.

[Exit Stage Left]

Notre Dame de Reims is arguably more important to France than the one in Paris, as it's where French Kings were crowned.

On December 16, 1431, Henry VI of England was crowned as "King of France" in the Notre Dame de Paris, according to a ritual similar to that established by his great-grandfather Charles V of France. This was an attempt to counter the coronation of Henry's uncle and rival, Charles VII of France, who had been crowned at Reims in 1429.

https://en.wikipedia.org/wiki/Reims_Cathedral

I'll be interested to follow the debates on 'authenticity' in the restoration. Modern fashion dictates a more traditional approach.

[T42]

France Info were just talking to an architect who would like to see titanium used for the spire framing, and maybe for the cover as well. Some other fellow was all for glass: tits on a bull IMO.

[Exit Stage Left]

A lot of the features of Notre Dame were re-imagined in the mid 19th Century.

In 1844 King Louis Philippe ordered that the church be restored. The commission for the restoration was won by two architects, Jean-Baptiste-Antoine Lassus and Eugène Viollet-le-Duc, who was then just 31 years old. They supervised a large team of sculptors, glass makers and other craftsmen who remade, working from drawings or engravings, the original decoration, or, if they did not have a model, adding new elements they felt were in the spirit of the original style. They made a taller and more ornate reconstruction of the original spire (including a statue of Saint Thomas that resembles Viollet-le-Duc), as well as adding the sculpture of mythical creatures on the Galerie des Chimères. The restoration took twenty five years.[24]

https://en.wikipedia.org/wiki/Notre-Dame_de_Paris

[T42]

I never much liked the spire anyway, but in restoring it they shouldn't break with the current style. Years ago the 13th-century Linlithgow church was vandalized in that manner:



That metal doo-dah was originally bright gold.

[Aunt Maud]

@ESL

FYI, the splits go 8" in from the butt end. This is not a defect, as any sawmill will saw the flared butt section off anyway.

One of your supposed defective stems, which according to your link are worth less than the cost of firewood.



8 months of sitting in the sun later and nothing. If it was a problem the splits would have propagated along the stem by now and split this 2' section in half.



As for buying timber.

The people who buy standing timber are coppice workers, who buy a set area of woodland timber for making coppice products.

Structural and joinery grade timber is sold forwarded out of the woodland and laying on the ground at the road. It is normally purchased by an agent and sold straight away to a mill as ordered or via auction. A timber merchant buys milled and dried timber through an agent at a wharf or travelling on a boat.

Carpenters send a cutting list to a mill and get what they are given according to the visual strength grade given after it is milled or if you have access to a qualified person, graded at the road head, but this is rarer than a rare thing as you need to allow for defects, sloping grain and knot type, position and the knot area ratio contained in the finished structural section and you can't do that unless you have X-ray eyes. So it's a guess as good as a guess could be.

Very rarely will a carpenter choose standing timber or buy stems at the road head and only if they are after a very specific type, size or shape or mill their own timber, which is what I have been doing for 15 years.

Such is the nature of the timber industry, which I have been involved in for over 35 years.

I guess we could all just google stuff to make ourselves look clever, instead of relying on first hand knowledge or proper qualifications. I'll let you have the last word on this..

Edit

Oh, I'll add. The soil those stems are laying on is the bank of the fjord, which is peat. They weren't grown there, but were grown at a much higher elevation within the woodland. They were put there by a 6 wheel drive forwarder after being harvested. It's the only spot where there is enough room to lay them out and has road access for the timber truck to crane them on and take them away.

(click to show/hide)

A bit of light joinery porn, incase anybody was wondering what the timber looks like when it is converted.......



Split off the log.



Quality control from the stick inspection operative.



The finished piece ready for seasoning.

[Man in a tree]

Re the earlier mention of "shaken" timber, I hadn't come across this before. Is it the origin of the expression used to describe being taken aback* by an experience, as in "I was shaken to discover ...".

*As in sailing ship being stopped in its tracks. I say, isn't language marvellous?

[Basil]

The bees survived!

[mark]

There seems to have been a fair bit of human error and fallibility (to put it mildly) in the fire safety plans for the cathedral.

https://www.nytimes.com/2019/04/19/world/europe/notre-dame-fire-safety.html?emc=edit_ne_20190419&nl=evening-briefing&nlid=1555877320190419&te=1

[Aunt Maud]

The Norwegians developed a sprinkler system for their stave churches which makes fine rain and covers the entire structure. They have also installed permanent fire hoses on site for anyone to begin fighting a fire at any time.




Relying solely on the char factor probably wasn't such a good idea in the end, but it has been standard practice to do so in historic timber building conservation for a long time.

[T42]

There seems to have been a fair bit of human error and fallibility (to put it mildly) in the fire safety plans for the cathedral.

https://www.nytimes.com/2019/04/19/world/europe/notre-dame-fire-safety.html?emc=edit_ne_20190419&nl=evening-briefing&nlid=1555877320190419&te=1

Seems to be a common failing. Applies to quite a few ancient buildings and some not so ancient. It's like everything else: doing nothing saves money, until it doesn't.