Treenails

Treenails, pronounced 'trennels' and called 'chevilles bois' or 'chevilles charpente' in French, are a key part of traditional carpentry, joinery and boat construction. Structural beams, rafters and braces are linked using mortise and tenon joints. That is where one element has a 'tongue' (tenon), which fits into a slot (mortise) in the other element. The joint is then fastened with a treenail, which is pushed perpendicularly through all the layers of wood by way of carefully drilled rabbet holes.

The grain of the treenail must be at right angles to the grain of the beam with the mortise, and the diameter of the treenail needs to be fractionally bigger than the hole into which it will be forced. In France both ends of the treenail generally protrude from the joint ie they are usually not cut flush. They are not glued. Treenails are structurally sound in spans up to 9 metres, but cannot be guaranteed beyond that.

A hard but flexible wood such as Robinia (Fr. Acacia) is traditionally used, but Oak and Chestnut can also be found (and would have been used before Robinia arrived in Europe in the 17th century). Treenails are subjected to tremendous force and must be able to withstand the natural movement in the carpentry joint as the Oak beams dry and twist. As a result they can't generally be removed, except by drilling out, and they certainly can't be reused, as they will have deformed in situ.

Before mechanisation treenails were made by splitting the wood then shaping with a drawknife. As a result they will be slightly faceted. Modern ones are about 35 mm in diameter and 24 cm long. The old ones in our house are variable and between 15 and 25 mm in diameter, and 21 to 24 cm long.

The smaller versions of treenails used in furniture making are known as dowels (tourillons in French) and are generally glued.

 

A broken treenail.

The photos are all of treenails in our attic, so are 19th century and handmade.

God Repairs the Roof

 

The process began with carefully removing some slates to expose a rafter.

Back in November Jean-Baptiste Dieu, a roofer from nearby Saint Flovier, came over to do a small repair job on our barn roof. Some of the roof crest (called le faitage in French) had cracked and chunks had slide down into the gutter.

Next a rope is passed around the rafter and a lightweight ladder tied in place.

It took him barely a couple of hours to do the job, even with me asking loads of questions about his work and taking photos. I was quite lucky to get him to come as he was working on his own temporarily, so a little bit of decorative mortar sculpture was something he could manage solo. Normally his team would include his teenage son, who is an apprentice and was away doing his college stint. Apprentices alternate between on the job training and formal instruction at college. Also on the payroll is an employee, who at the time was in hospital with a collapsed lung (not Covid19 related).

Mixing lime mortar.

Jean-Baptiste is a master craftsman, which means that he has completed a really challenging project known as a chef d'oeuvre. He tells me that his is kept upstairs in the town hall in Loches, and that if I go in and say he sent me someone will take me up to see it. I will certainly be doing that one day once the pandemic allows.

The mortar is carried to the ladder.

We have seen master works a number of times and they are remarkable pieces, often whimsical as well as demonstrating the artisan tradesperson's skill.

And then up the ladder.

To see some fine examples you can go to our blog post on The Musée de Compagnonnage, Tours [link] and Good Value in Paris Part 3 [link] which is about the restaurant run by the Master Carpenters Guild.

Sculpting the crest repair.

The work cost €400 plus tax.

Adding the final careful touches.

Descending the roof.

Carefully sliding the slates back in place.

The slates (Fr. les ardoises) are removed or replaced by turning the slate hook (Fr. crochet ardoise) and sliding a sheet of metal underneath then manoeuvering it so that the slate follows.

I asked Jean-Baptiste how the slates were removed if they were fastened with the old fashioned traditional copper nails. He very kindly opened up his tool kit and took out a long handled tool with a forked end for grabbing on to the nails. He said the nails were always hammered in at an angle which made extracting them a bit easier. Somehow I failed to take a photo of the tool though.

************************************************

For details of our private guided tours of chateaux, gardens, wineries, markets and more please visit the Loire Valley Time Travel website. We would be delighted to design a tour for you.

We are also on Instagram, so check us out to see a regularly updated selection of our very best photos. 

Regional Roof Tiles

I've been talking about roofs and tiles to various people recently, so I thought I would refresh and repost something Simon wrote in October 2008.

*****************************************************

Flat terracotta tiles in La Guerche.

Preuilly sur Claise is on or close to a number of borders. At the time our barn was built it was on the border between England and France. During the Second World War it was close to the border between Vichy and Occupied France. Now it is very close to the border between the départements (counties) of Indre, Indre et Loire, and Vienne.

It is also close to another less formal border - that of roof tiles.

In Preuilly we have flat tiles, known as tuiles plates. These tiles are traditionally made in terracotta (in French terre cuite) and are found in all places north and east of us. The tiles are hung by a little tag on horizontal battens, which you can see quite clearly in this photo of our roof under repair.

 Our barn roof being renewed with flat terracotta tiles.

However - travel only 25 kilometres toward Poitiers and you will see roofs of canal or mission tiles (tuiles canal). These are also made from terracotta, but are slung in vertical battens, with one tile on its "back", with another tile upturned over the top. This makes everything look very Roman, or mediterranean. These tiles are in St Germain de Confolens, in the Charente.

Of course, if you had a lot of money when you built your house, or subsequently came into money and wanted everyone to know about it, you have a slate roof. Like a lot of buildings in Preuilly, our barn has a slate roof facing the street, but a tiled roof where it doesn't show.

************************************************

For details of our private guided tours of chateaux, gardens, wineries, markets and more please visit the Loire Valley Time Travel website. We would be delighted to design a tour for you.

We are also on Instagram, so check us out to see a regularly updated selection of our very best photos. 

Preuilly Roof Styles

Recently I've had a number of conversations about terracotta tiles, both for roofs and floors. I've also discussed the problem of modern gutters exacerbating the problem of buildings cracking in the dry, which many people have experienced in the last couple of years. Some local authorities, such as Charnizay, have declared a catastrophe and residents are being advised to contact their insurance companies, who will be obliged to cover the costs of repairs. Preuilly has not gone down this route and has presumably been less affected by this year's drought. So I thought I would refresh and repost something I wrote in December 2016.

****************************************

Flat terracotta tiles.

Flat terracotta tiles on a roof, with some age, lots of lichen and moss. Theoretically you should clean off the growth to keep your roof in good condition, but hardly anybody bothers. Note the lack of gutter, which is traditional for here. Gutters are rather a modern affectation, and the old buildings can suffer if the soil around them dries up due to water off the roof being collected and piped away rather than being allowed to fall on the ground about half a metre beyond the walls.

Slate tiles and metal flashing and finials.

A nice smart slate roof on a tower peeps out above other long low roofs of slate or flat terracotta tile. The tower roof is finished with 'zinc' (actually pewter type alloy or galvanised steel). There is a decorative pattern in the slates (usually created by hanging the slates on a different alignment) and a monogram on the chimney of forged iron.

Another flat terracotta tile roof (with a bit less lichen and moss). 

On the right is a special curved tile with is for ventilation.

************************************************

For details of our private guided tours of chateaux, gardens, wineries, markets and more please visit the Loire Valley Time Travel website. We would be delighted to design a tour for you.

We are also on Instagram, so check us out to see a regularly updated selection of our very best photos. 

The March 1 2018 Snow Event

On Thursday March 1 2018 we awoke to a couple of centimetres of snow. This appeared to catch the nation by surprise and cause a lot of media chatter, despite the fact that it had been forecast by the meteorologists.

The driveway.

 Cat footprints and another animal that puts all its feet in the same print, giving the appearance of having been a one legged creature hopping up the driveway. This was photographed at about 8am, by which time Ghislaine had already cleared the street in front of her house.

 Looking up the street.

 The courtyard.

 A mini snowman on a front window ledge.

 Dotty and her organic veg braving the snow.

Dotty was one of only two market stallholders who turned up. She commented that snow didn't put customers off nearly as much as rain does. However, the real reason I took this photo is that in the background, with the Copra van just passing, is a woman in her pyjamas and a pink dressing gown vigorously sweeping her footpath clear of snow.

The only other stall, with Dotty borrowing their scales because she forgot hers in the excitement.

 Roofs, including ours.

Nurturing Local Heritage Conservation Expertise

For the current major conservation work at the Chateau of Azay le Rideau, the Centre des Monuments Nationaux (CMN) has appointed local firms. They include Hory-Chauvelin (stone cutting, scaffolding, masonry, plastering and tiling) from Avoine, the Rolland-Réau group (stone treatment, sculpture) from Montlouis and the joinery Guérin Brothers from Pouzay. The first two have worked together on previous heritage conservation projects such as the Hôtel Gouin in Tours. Of the 9 contracts 6 have been won by local Tourangeaux firms.

Openings in the screen allow materials to be hoisted up and visitors to get a glimpse of the work behind.

Chrystelle Laurent, the senior curator, is at pains to point out that this is not parochialism, but because they are the best. The Touraine is a land of abundant limestone and therefore has a high concentration of masons and other expert artisans, so the choice is extensive. The CMN wants the work to be a showcase of the local skills with a level of excellence that is reknowned world wide.

The mirror pond that the chateau sits in creates logistical problems, solved by a raised platform created to gain access to the works from the rear of the building. 

Like Olivier Rolland, a sculpture conservator from Montlouis, many of the conservators and artisans have put their expertise to the test at the most prestigious heritage sites in France. Versailles, the Louvre and Chenonceau have all benefitted from the skills of these little known artisans who work in the background, unacknowledged except by fellow heritage professionals. They run businesses to be sure, but they also work for the prestige of gaining a contract such as at Azay. They are excited by the project and love the chateau.

I notice that they have planted bulrushes in the pond, presumably in acknowledgement of the restoration of Philippe Lesbahy's bedroom with its rush matting wallcoverings.

Olivier examines each stone carefully, checking if lichen is causing damage and needs to be removed or treated. His objective is to save as much original stone as possible and slow down further damage. Around him other teams of specialists are checking lead finials and treating wood. It's a huge restoration job.

Scaffolding across the front of the building, with a lifesize photo of the staircase printed on the protective screening.The screening also forms a weatherproof 'umbrella'.

Chrystelle notes that these artisans carry a particularly French know-how and present it to the world (she is, after all, a self-confessed 'child of Colbert'...) This work is also a means of ensuring these highly skilled individuals can earn a living.

Explanatory panel at the base of the chateau, talking about the slates and finials.

The work entails:

• 25.5 m high scaffolding.
• 4125 m² of stone repointed.
• 5425 m² of facade.
• 35 m³ of new oak carpentry.
• 1838 m² of new roof.
• 75 tonnes of slate.

I calculate that this means the roof alone (excluding carpentry) will cost at least €130 000.

The Biencourt's sitting room, as it was a few years ago.

Once the exterior is completed the next project is to improve the 19th century rooms on the ground floor. These rooms acknowledge the legacy of the Biencourt family, the last private owners of the chateau. In the next 2 years over a hundred objects from the CMN archive stores will be heading for Azay. Crockery and cookware owned by the Biencourt family will return to their old home and portraits from the 16th century hung to partially reinstate the family's collection. Textiles from the period will be conserved and rehung too, to return the feel of the rooms to how they were in the past. A highlight will be the velvet curtains set with gold lilies, with which these rooms were dressed at the time.

Article about the restoration in La Nouvelle République newspaper (in French).

Touraine Buildings Terminology: Roofs Part I

General Terminology Part I
General Terminology Part II
General Terminology Part III

Tiles and slates on the same roof slope -- a sure sign of repair.

Touraine Buildings Terminology: Facades Part I
Touraine Buildings Terminology: Facades Part II
Touraine Buildings Terminology: Facades Part III

 Some very steep slate roofs.

In the majority of cases, roofs of two symetrical slopes are favoured, inclined at an angle of between 40 and 45°.

 Slates covering the walls as well as the roof.

Two sorts of materials are generally used in the Touraine: small flat terracotta tiles and natural slate.

A complex of buildings with a mixture of tiles and slates on different slopes.

Materials (les materiaux)
The presence of tiles and slates on the same slope of a roof would not have been the way it was done traditionally, but it is a style of roof repair which it is better to avoid when the entire roof is redone.

A tile roof.

Flat Tile (la tuile plate)
During the 19th century, local artisanal tile factories experienced a boom. Flat tile became the material of choice, still visible on numerous buildings in our towns and villages. It is as well represented on industrial buildings as on dwellings. The roofs are made of small flat tiles in red-brown or orangey-red, depending on their source and state. That's why tile roofs aren't very homogenous and the effect is to blur the colours.

 A tile roof.

One peculiarity of the Touraine persists in Richelieu, where you can sometimes find a tile called tige de botte ('boot upper').  It looks like a roman canal tile, but doesn't have the same dimensions.

 Slate treated decoratively and solving a practical problem at the same time.

Slate (l'ardoise)
Coming from the Angers basin and transported up the rivers, slate was reserved for the nobility. If its light weight rendered it easier to transport on the river, its delivery was nevertheless costly. Over the course of the second half of the 19th century slate little by little became more widespread along the banks of the Loire, in the centre of towns on maisons de maître (elegant town houses), before spreading into the countryside.

 Fish scale patterned decorative slate.

Sealed by metal sheets, slate can be adapted to all roofs with a slope between 30° and vertical. They are attached with a nail or a hook, preferably black in colour.

 Slate can be shaped into many complex curves and angles.

In Conclusion
To obtain the best effect it is recommended for restorations to choose traditional flat tiles. The advised density is 60 to 75 tiles per m² minimum, depending on the pitch. It is to be regretted that today, tiles are tending to disappear in favour of slate.

 Slate and tile roofs, with the middle roof showing the metallic flashing which ensures the angles are waterproof.

Touraine Vernacular Buildings Terminology Part II

Part I is here.

'Associated with the Loire, the ancient architectural heritage is a constituent element of the Touraine (Loire Valley) identity. It merits particular attention in its treatment, and that of its surrounds, both built and vegetative.'

Une baie secondaire.

A secondary bay -- a small opening, usually a 4 paned window.

Une fenêtre.

A window.

Windows are typically a pair of casements (deux vantaux) which open inwards (à la française).

They should have the following dimensions:

90 x 135 cm (6 panes, like this one).

100 x 145 cm (8 panes).

110 x 160 cm (10 panes).

This one has shutters (volets) in a 19th century louvred style known as persiennés.

Une lucarne engagée dans le mur.

A wall dormer (set so that the front continues the plane of the wall and the bottom breaks the line of the cornice). This one is hip-roofed.

Les lucarnes sur versant.

Dormers (these are hip-roofed).

Les montants.

Jambs (the frame that holds the window or door).

Un oculus.

An oculus window.

They should be 40 x 50 cm.

**************************************************************

Loire Valley Nature: A new entry has been added for Whorled Caraway Carum verticillatum.
A new entry has been added for Breckland Thyme Thymus serpyllum.
Photos of the all important seeds have been added to the Pepper-saxifrage Silaum silaus entry.
Photos have been added to the Bee Flies Bombyliidae entry. 
A photo has been added to the Adonis Blue butterfly Polyommatus bellargus entry. 
A photo has been added to the entry on hunting. 
A new entry has been added for Brown Hare Lepus europaeus. 
A new entry has been added for Rustyback fern Ceterach officinarum.