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External Thermory® Cladding

Thermory® Cladding

We have recently added the Thermory® Spruce collection to our cladding range. Thermo treated timbers have been heated and steamed at temperatures of up to 215°C in computer-controlled kilns to give timbers, that are not typically known for their durability, the credentials of class 1 and 2 hardwoods. Thermory® processes are entirely chemical-free and are only applied to responsibly harvested raw materials. With nine styles/colours to choose from, our external cladding range allows you to ensure your project is finished to the highest standard.

Thermory® External Cladding Photo Gallery

Thermory® Thermo-Treated Pine External Cladding
Thermory® Thermo-Treated Pine External Cladding
Thermory® External Thermo-Treated Ash Cladding

View more photos in the Thermory® External Cladding Photo Gallery

What is Thermory Cladding?

Thermo-modified timbers offer an alternative to standard impregnated timbers and is an ever-popular method as it is a chemical-free process that makes use of timber sourced from well-managed American and European forests (endangered rainforest wood is not used) and provides no waste.

Thermo-treated Pine and Ash have been modified with steam and computer-controlled kilns which exposes the timber to intense heat treatment (temperatures up to 215°C) making the timber less likely to rot, warp, bow, twist or shrink due to its higher dimensional stability and lower moisture content.

The end result of thermo-treating timber is the transformation of responsibly sourced and fast-growing pine, a softwood, into a decking and cladding material with class 2 durability credentials equal to the hardwoods.

This Thermo-treated range of products includes Decking, Flooring and Internal and External Cladding. All offer excellent durability, outstanding value and a high end, contemporary finish.

Like all-natural timber, Thermory® will begin to gently weather down once exposed to the elements. Such weathering includes; an attractive silvering/greying and the development of small, surface hairline cracks. Whilst many prefer to allow this appearance to develop, it can be kept minimal through regular application of Thermory® Thermo-wood oil. These boards can also be sanded back at any time to restore the original eye-catching tones.

C7J Thermory® Pine Cladding with PaC-System® Fitting System

Thermory® Sub Structure battens feature pre-installed hidden fastening that easily clips into the pre-machined grooves on the reverse of the chosen boards. As with all of Thermory’s® products, their pine C7J cladding boards have been thermo-treated; a chemical-free kilning process that ensures durability and rich colours.

Thermory® Pine cladding is available in several profiles which match the different Thermory® clip systems

Drift Collection External Cladding

The first in the Thermory® rebel collection, Drift unleashes the look of reclaimed wood but without the unknowns. Unrivalled in durability and rot-resistance these unique boards give a naturalistic and washed ashore vibe.

With both internal and external cladding available it really is possible to find contemporary coloured cladding that best suits your needs and style.

Cut from Picea Abies Spruce, treated without chemicals, and finished with a multi-layer Water-based acrylic Drift finish, these Eco-friendly boards have outstanding durability with a fantastic price tag to match.

About Thermory

Thermory® only use high-quality spruce for their cladding boards, sourced from well-managed forests in Finland and Russia where good growing conditions and strict drying standards are enforced.

The Drift collection has been subjected to ‘intense’ thermo-treatment’, which heats and steams materials up to a maximum temperature of 215°C, ensuring maximum stability and a dark and rich colouring throughout the timber. This Eco-friendly and chemical-free process also ensures a low moisture content, removes remaining resin, reduces splitting, reinforces the timber and improves durability against decay. The end result is the transformation of responsibly harvested and rapid growing spruce, a softwood, into the perfect cladding material with class 1 durability credentials making it equal to the hardwoods.

Product Information

Each piece of timber board from the Brushed Spruce Drift collection is treated with fungicide to stop fungal growth between layers of tint and each backboard is oiled. In addition to oiling each board has a tongue and groove profile to ensure a flush finish against any surface.


Each board can be fitted using stainless steel nails or screws, and to avoid moisture accumulation, sufficient airflow is needed behind the boards. For very wet areas it is optional to use 1 mm spacers between the timbers.

Maintenance - External Cladding

Like all timbers, Thermo-treated boards for external use will begin to gently weather once installed. Drift finish, however, is estimated to last between 3 to 5 years without any major alteration in appearance. It is to be expected that surface hairline cracks may appear in the boards, this is a natural occurrence in timbers installed for external use.

Key Features

Some features of the interior and external cladding boards to note are; its consistent appearance, unique colouring, outstanding grain detailing, dependable stability, rot-resistance, significantly reduced moisture absorbency and, perhaps most noteworthy of all its multi-layered water-based acrylic Drift finish.

Colour Variants

Platinum & Black Pearl are two colour variants available in Round Wood’s external range. Both measuring at 175 mm face.

Round Wood also has four colour variations in their interior range; Sandy Pearl, Brandy, Gunpowder & Silver Storm also measuring at 175 mm face.

Round Wood of Mayfield
Newick Lane
East Sussex
TN20 6RG

Opening hours:
8am-5pm Monday to Friday
8:30am-12:30pm Saturday