Brimstone Ash Cladding

Brimstone ash Cladding from Vastern Timber

• Thermally modified British ash
• Sourced from legal and well-managed woodlands in England and Wales.
• Supplied by Vastern Timber (sales@vastern.co.uk)
• Grade BS1186-3 Class 1 / EN942:2007 J10
• Finished thickness of 20mm
• Overall finished widths 70mm / 95mm / 120mm / 145mm
• Random lengths 1.5mt – 3.0mt+
• Available in various profiles
• Moisture content of 4 – 6%
• Durability EN350-2 Very Durable. Class 1 (Above ground use only)
• Supplied uncoated. No treatment required.

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Appearance
Brimstone ash has a consistent chocolate brown colouring with a strong grain pattern. Cladding boards may contain occasional small sound knots. 

Weathering
The modification process removes most natural extractives resulting in relatively consistent weathering, largely free of staining. Weathering to a grey colour occurs more quickly than for non-modified timber

Desired service life
Occasionally wet: 60 yrs. Frequently wet: 30 yrs.

Movement class
Small 

Resistance to impact
Medium 

Working properties
Thermally modified woods are more brittle than untreated wood. Care should be taken when cutting and nailing to prevent chipping and break out. Pre-drilling is advised.

Density
563 Kg / M3

Extractives
The modification process involves no chemicals and most natural chemicals in the wood are removed during the process. Thermally modified wood can be treated as inert.

How to fix Brimstone ash cladding
Pre-drill and fix boards with stainless steel nails or trim head screws through the face or through the tongue of suitable profiles.

Alternatively use a second fix nail gun and insert two 16 gauge brad nails, suitable for external use, per batten at opposing angles.

Always pilot drill fixings and countersink screw heads.

Create a 2mm expansion gap between following boards.

For more information, visit the resource centre

Recommended battens for Brimstone cladding
Profiled Thermowood or treated softwood battens are recommended for use behind Brimstone ash cladding.

The minimum thickness of primary battens should be 40mm. Horizontal battens to have an angled top face to shed water.

Find out more about our Thermowood batten system

Batten spacing for external timber cladding
400 – 500mm

Fixings for Brimstone ash cladding
Only use stainless steel fixings for external cladding.

For fixing Brimstone ash cladding we recommend 50mm ring shank nails or trim head screws for face fixing and 40mm for hidden fixing through the tongue.

If using a nail gun to fix your cladding boards select 50mm 16 gauge brad nails, suitable for external use.

When to fix Brimstone ash cladding
Brimstone ash is very stable and can be installed year round.

Resistance to fixing
Low. Brimstone ash is brittle and should be treated with care.

We machine timber cladding to the profile of your choice. View our full range of cladding profiles.

We recommend the following profiles for Brimstone ash.

While the utmost care has been taken to provide accurate information, Vastern Timber shall not be held responsible for any consequences arising from any errors or omissions on this website nor for any damages resulting from the use of the information.