Tours by appointment onlyFull Covid-19 Update

0 items


Vertical Grain Siberian Larch Cladding

Vertical Grain Siberian Larch

Vertical Grain Siberian Larch (VG SILA) is a naturally durable and aesthetically pleasing product. It is particularly popular for projects with a requirement for both timber cladding and decking; using VG SILA can create a consistent look throughout the exterior of the project. 


Russwood’s VG SILA boards come in a warm mix of colours, from light reddish brown through to golden browns. The grain of the wood is exceptionally straight and the annual rings are close together. Growth rings mainly run in straight lines on the surface which means minimum risk of surface checking and minimum risk of splinters forming as a result of delamination between the growth rings. When exposed to the elements and sunlight, the colour of the cladding will change to an even shade of grey. If used in a project alongside SILA decking, the weathering of both products will offer consistency of the overall look over time.

VG SILA is supplied as a mix of the highest Siberian Larch grades with approximately 70% being virtually clear grade (knot free), resulting in a clean, contemporary timber cladding option.

VG SILA is comprised of vertical and semi-vertical grain boards. “Vertical grain and semi vertical grain” refers to the way in which the Siberian Larch is sawn perpendicular to the trees annual growth rings, in order to create a highly dimensionally stable product whilst also achieving a remarkably clean look. Cut from the heartwood with growth rings ranging from 30 – 90°, VG SILA is more stable than flat sawn boards.


  • Aesthetically refined and naturally durable cladding
  • Particularly special when combined with FassadenClip® fixings
  • Ideal for seamlessly blending cladding and decking to weather naturally, or with SiOO:X for an accelerated weathered effect and additional water repelling benefits
  • Natural durability; no chemical treatment required
  • Russwood’s SILA is FSC®-certified, meaning that it is sourced from well-managed forests
Siberian Larch
Density* Kg/m3 at 18% moisture content unless otherwise stated
628 - Very Dense
Very Good
Durability Class* 1 is 'Very Durable' > 5 = 'Not Durable'
Very Few
Suitability for Factory Coating
Environmental Certifications
Modified Timber
Price From** per m² excluding VAT

Grades and Specification

  • Graded to BS1186-3 Part 4 CSH/1; each board is centre pith free, one face will be sap free, through knots have a maximum 25mm diameter and resin pockets although not prevalent are a natural characteristic of Siberian Larch
  • Chipped out knots permitted up to a maximum of 25mm diameter
  • End checks permitted not longer than 1.5 times width of board
  • Kiln-dried to moisture content of approximately 16-18% (+ / – 2%)
  • High density of approximately 628kg/m3 at approximately 16 – 18% moisture content
  • PAR, (Planed all round) 4 chamfered edges – RW212 profile
  • Lengths up to 5.1m supplied in running meters
  • FSC®-certified product sourced from sustainable forests
  • No limitation of splay knots
  • Each board is sap free on face

NBS Specification

For advice on completing the NBS H21 for VG SILA please get in touch with our project team.


One of the primary benefits of SILA as a cladding material is that it is one of the toughest and most durable softwoods. It is naturally durable, being rated as Class 3 according to BS EN 350-2. This means that it does not require any chemical treatment.

This natural durability is the result of resin and extracts in the wood, combined with a high density, which reduces the wood’s vulnerability to rot, decay and insect damage.


SILA is a dense timber, classified by BS EN 350-2 as approximately 628 Kg/m3 at a moisture content of approximately 16 – 18%. As such, it is not easily damaged.


Russwood’s VG SILA is more dimensionally stable than standard at sawn offerings. Flat sawn boards can move up to 50% more than vertical grain boards. This reduced propensity to move means minimal shrinkage and expansion.


The standard VG SILA cladding profile is a 27 x 92mm square dressed with bevelled edges. Lengths up to 5.1m supplied in running meters. Please note that cladding is supplied as a linear meterage based on random stock lengths at time of picking order. Other sizes may be available on request.

Surface Finishes

We can produce Vertical Grain Siberian Larch in a Planed finish – boards are run through our planing mill to create a smooth, dressed finish.


Due to the natural durability and beauty of VG SILA cladding, it is generally left untreated to weather to a consistent shade of grey. SILA is suitable for factory coating in SiOO:X, a breakthrough silicone technology, to provide a genuine silver lustre whilst still seeing the figuring of the Larch. SiOO:X creates a weathered appearance at an accelerated rate. Following application, all areas, regardless of protection and exposure, take on a consistent tone which provides a solution to differential weathering. For further information about SiOO:X click here.


How timber is fixed is fundamental to it’s long term performance in terms of both appearance and durability. We offer a range of fixings and systems to make cladding look better and last longer. These systems can be written into the NBS H21 specication. For enhanced durability and improved stability use FassadenClip® for a secret fix solution or, for a face fix option, use KompeFix® with L-Go Fix® screws.

Virtual Samples

Click on the 3D icon to view virtual cladding sample. Tilt and zoom in on the sample to view the texture, grain and colour of the boards and use the highlight feature to see how light and shade affect the aesthetic.

Profile Options

VG SILA can be produced in the following profile.

Sizes are subject to change in response to changes in moisture levels. Cladding / decking will be kiln-dried to approx. 16-18% prior to machining, but may vary between production and installation on site. Cladding / decking will be dispatched at given sizes, but a margin of error should be used when producing cladding / decking layout drawings for expansion and contraction in the timber.

Surface Finish Options

We produce Vertical Grain Siberian Larch in a Planed finish – boards are run through our planing mill to create a smooth, dressed finish.


Planed boards are run through our planing mill to create a smooth, dressed finish.
Learn more

Coated Options

Due to the natural durability and beauty of VG SILA cladding, it is generally left to weather naturally. It is, however, suitable for factory coating with SiOO:X, coloured finish or Fire Retardant.


A consistently weathered appearance at an accelerated rate, available in orginal and pigmented versions.
Learn more

Factory Coated

A high quality pre-painted coloured finish with optimal long term product performance.
Learn more

Recommended Fixings

How timber is fixed is fundamental to its long-term performance in terms of both appearance and durability. These are the fixings recommended for use with VG SILA.

L-GoFix® A2 Screws

Face Fix

Cladding screw for effective fixing and neat detailing.

Learn more


Secret Fix

An innovative secret-fix solution for open rainscreen cladding.

Learn more

Russwood Battening System


Environmentally friendly, engineer-assessed, method of fixing timber cladding.

Learn more


Face Fix

Compensation strip designed to prevent direct contact between timber elements.

Learn more

F-BohrFix® ZB Screws

Secret Fix

For optimal fastening of tongue and groove cladding.

Learn more

L-BohrFix® A4 Screws

Face Fix

A highly corrosion resistant screw for special applications.

Learn more