Robinia shingles – durable roofs and walls
Robinia series · Need: “covering a roof or a façade”
The wooden roof tile, in Europe’s most durable timber.
The shingle — the wooden roof tile — has clad roofs and façades for centuries. Made from robinia — also known as black locust, and often sold as acacia (Robinia pseudoacacia) — it adds the durability of Europe’s most resistant timber to the charm of the traditional shingle, with no treatment at all.
Our shingles are sawn and quarter-sawn for maximum stability; they are laid overlapping on a ventilated substrate, on roofs and façades alike.
The shingle, a wooden tile making a comeback
Tavaillons in the Alps, essentes in Normandy, shingles in Quebec: the wooden tile is a tradition wherever the forest was close at hand. The historical benchmark in France is sweet chestnut. Robinia does even better: harder and more durable when exposed to the weather, it brings the same living look — honey-coloured at first, silver-grey later — with greater longevity, and no treatment or compulsory maintenance.
Why our shingles are sawn — and quarter-sawn
Two manufacturing choices determine the quality of a robinia shingle. First, sawing: traditionally, shingles were split (shakes) — but robinia splits poorly (very hard timber, lively grain) and its natural durability makes splitting unnecessary. Split shingles are also thicker than sawn ones: more material and more waste — so more expensive — and more load on the roof structure. Sawing produces sized, consistent, lighter shingles that are quicker to lay. Acacia Bois produces sawn shingles only. Second, the radial cut: the shingle is quarter-sawn, with the growth rings perpendicular to the face. It is the most stable cut there is — the timber stays flat, without cupping — exactly what you need from a small piece exposed to constant cycles of rain and sun.
Installation: overlap, ventilation, stainless steel
Overlapping. Like tiles, from the bottom up, each course covering the one below so that water never meets a through joint. The overlap is adjusted to the pitch — the shallower the pitch, the greater the overlap.
On a ventilated substrate. On battens, with a continuous air gap behind the shingles: it is the ventilation that dries the timber after rain and makes the installation last, on roofs and façades alike.
Fixings and setting-out. Stainless steel fixings are essential — robinia, being slightly acidic (pH ≈ 4.5), corrodes ordinary steel — and pre-drill thick pieces. The laying plan — the setting-out — fixes three values: the exposure, the length of shingle that remains visible once the course above is laid (140 mm in standard installation); the headlap, the part hidden by the courses above; and the batten gauge, the centre-to-centre distance between the battens that carry the shingles. The sawmill sets them according to the pitch and the exposure to the weather.
Delivered fresh. Our shingles leave the sawmill as fresh timber, or at most slightly air-dried: they finish drying in place, on the roof. This is traditional shingle practice and is in no way a defect — the shrinkage that follows installation is absorbed by the three-layer overlap, since each shingle is fixed independently. Two practical consequences: store the bundles flat, under cover and ventilated, without leaving them strapped in full sun; and lay them within a reasonable time after delivery rather than letting them dry in a stack.
Dimensions. Our shingles are 45 cm long, 7.5 to 15 cm wide (random widths, as tradition has it) and 12 to 14 mm thick, wedge-shaped — the visible part, the thickest, is 14 mm. They are laid in three layers, with an exposure of 140 mm, on pitches of 18° and above.
Quantities for your roof. First, remember the simple rule: in three-layer installation, you need about 3 m² of shingles laid flat to cover 1 m² of roof. In concrete terms, a bundle of 120 shingles represents 4.95 m² laid flat, or 1.65 m² of finished roof, weighing 35 kg per bundle and about 21 kg/m² once laid — allow 5 % extra for trimming. A pallet of 40 bundles covers 66 m² of roof and weighs about 1.4 tonnes.
The pitch changes the numbers. The flatter the roof, the more slowly water drains away: the overlap then has to be increased — a reduced exposure, or even a fourth layer — and the number of shingles per square metre rises by a good third; that is why standard installation stops at an 18° pitch. Conversely, a steep pitch keeps the 140 mm exposure and makes the roof last longer. Finally, measure along the slope — the actual length of the roof pitch — not the plan area: at a 30° pitch, 10 m² of plan area makes 11.5 m² of roof; at 45°, 14 m².
Roofs, façades, shelters: where the shingle excels
On roofs, on steeper pitches; on façades, where it replaces conventional cladding with a unique texture; and on all kinds of small outdoor buildings — cabins, garden sheds, henhouses, covered furniture. We have made bus shelters roofed with robinia shingles, exposed to every season without maintenance. Left natural, the shingle greys evenly; its strength stays unchanged.
Key points
· Robinia shingle = a use class 4 (EN 335) wooden tile, with no treatment — more durable than sweet chestnut, the historical benchmark.
· Sawn, not split: robinia splits poorly and its durability makes splitting unnecessary; sawing gives sized shingles.
· Quarter-sawn (radial cut): growth rings perpendicular to the face, maximum stability, no cupping.
· 15-year guarantee, FSC® 100 % certification on request.
· Quantities: about 3 m² of shingles laid flat per 1 m² of roof · 1 bundle = 120 shingles = 1.65 m² laid · 1 pallet = 40 bundles = 66 m² · +5 % for trimming.
· Delivered as fresh or slightly air-dried timber: drying finishes on the roof, and shrinkage is absorbed by the overlap.
· Overlapping installation on a ventilated substrate, stainless steel fixings, pre-drilling — setting-out agreed with the sawmill.
· 45 cm × 7.5–15 cm, 12–14 mm thick (visible part 14 mm) — laid in three layers (140 mm exposure), minimum pitch 18° — allow ~73 shingles/m², i.e. 7 bundles for 10 m² of roof.
· Roofs, façades, shelters: it greys, it does not weaken.
Frequently asked questions
Sawn shingles or split shakes?
For robinia: sawn. Splitting, traditional for sweet chestnut, was justified by the durability that the continuous grain provided — but robinia is already naturally use class 4, and it splits poorly (very hard timber, lively grain). Sawing produces sized, consistent shingles that are quicker to lay, with no loss of longevity. Bear in mind, too, that a split shingle is thicker: more material and more waste — so more expensive — and a greater load on the roof structure.
Why quarter-saw the shingles (radial cut)?
Because it is the most stable cut: the growth rings run perpendicular to the face of the shingle, and shrinkage takes place flat, without cupping or warping. For a small, thin piece subject to constant cycles of rain and sun, this stability is what keeps a roof flat and watertight.
How long does a robinia shingle roof last?
Several decades without treatment: robinia is Europe’s most durable timber (use class 4, durability class 1–2 EN 350), and it outperforms sweet chestnut, whose traditional roofs already lasted for decades. Our shingles also carry a 15-year guarantee, and their natural durability is class 1–2 (EN 350-2) — the highest level in the standard. The exact service life depends on the pitch, the ventilation and the exposure — discuss your project with the sawmill.
How many shingles do you need to cover 10 m² of roof?
In standard three-layer installation (140 mm exposure, pitch of 18° and above), allow about 73 shingles per square metre, or roughly 730 shingles for 10 m² of roof. As each bundle of 120 shingles covers 1.65 m² once laid, you need 7 bundles — 6 bundles would cover only 9.9 m², and the 5 % for trimming is included in the seventh. That is about 245 kg of timber to lift onto the roof. Two pitfalls to avoid: below an 18° pitch, standard installation is no longer enough (increased overlap, waterproof underlay) and the number of shingles rises by a good third; and it is the area measured along the slope that counts, not the plan area — at a 45° pitch, 10 m² of plan area represents 14 m² of roof. Send the pitch and areas to the sawmill: the exact setting-out and the number of bundles are part of the quote.
Can you clad a façade with shingles?
Yes — it is even one of their finest uses: laid overlapping on ventilated battens, shingles replace conventional cladding with a unique scale-like texture. We have made entire façades and bus shelters this way, exposed all year round without maintenance.
Are robinia shingles delivered dry?
No, and that is deliberate: they leave as fresh timber, or at most slightly air-dried, and finish drying once laid. This is traditional shingle practice — drying shrinkage is absorbed by the three-layer overlap, since each shingle is nailed independently. Two precautions on delivery: store the bundles flat, under cover and ventilated, without leaving them strapped in the sun, and lay them within a reasonable time rather than letting them dry in a stack — a shingle that dries stacked and tightly packed will warp.
Further reading
Reference guide: “Robinia outdoors – the complete guide”.
See also: “Finger-jointed robinia decking and cladding – stable and durable” · “FSC and ISO 9001 – Acacia Bois certifications” · “Greying and maintenance of robinia”.
Our products: Robinia shingles (shakes) · Finger-jointed cladding board · Edged boards · Large posts.
Contact: A roof or façade to cover? Send us the area, pitch and exposure: the sawmill will draw up the setting-out and the quote.
Disclaimer. Non-contractual article, provided for information only (photos and drawings included). Robinia is a natural material: the values given are orders of magnitude and may change without notice; in case of discrepancy, only the product’s technical data sheet and the general terms of sale apply. Always check the regulations that apply to your project.
© Xylo Impact SRL — all rights reserved, products marketed under the Acacia Poles brand. Any reproduction, even partial, is prohibited without prior authorisation.
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