Supplied by Arch Wood Protection South Africa

Wood shines as a sustainable and renewable construction material which offers great aesthetics and structural strength. Image by James Fitzgerald | Unsplash

Wood shines as a sustainable and renewable construction material which offers great aesthetics and structural strength. Image by James Fitzgerald | Unsplash

The concept of green and sustainable building is not new but has never been more important when making material choices. This is where wood shines as a sustainable and renewable construction material which increases thermal efficiency and offers great aesthetics and structural strength.

While it is loved for its warmth and beauty, it can also be vulnerable to the effects of the weather, wood decay and insect attack.

JJ du Plessis, senior business manager at Arch Wood Protection South Africa, said, “As a global leader in wood preservation, Arch Wood Protection supports sustainable building through the promotion of quality treated wood. Because of its ability to store carbon throughout its lifetime, wood plays a vital role in reducing the carbon footprint of buildings. But we also understand that equally important is the need for green rated wood preservatives that contribute to the green building rate system”.

To meet the emerging demand for green rated products, Arch Wood Protection introduced two globally acclaimed wood preservative treatments to the South African market – namely Tanalith E, for use in building, garden and structural wood treatment in the H2 to H5 hazard classes, and Vacsol Azure, for primary use in residential and commercial applications.  Both preservative treatments are subject to Arch Wood Protection’s broad global regulatory expertise, toxicology and analytical chemistry skills and satisfy green building and sustainability standards.

Green Star rating

After undergoing rigorous assessments, both TanalithE and Vacsol Azure preservative were independently verified by Ecospecifier Global as likely to contribute to the achievement of Green Building rating credits. Du Plessis added that the growing interest in Green Star certification in South Africa has placed Tanalith E and Vacsol Azure in a good position to provide professionals with green rated options in specifying treated wood products.

“This endorsement has been instrumental in building product confidence and is a clear indication of our stance and commitment to provide solutions that ensure a sustainable future for generations to come,” said du Plessis.

<Subheading3> First metal-free light organic solvent preservative

In 2012, Vacsol Azure wood treatment made its mark in South Africa as the first metal-free Light Organic Solvent Preservative that provides treated wood with greater dimensional stability than conventional water borne preservative products. Eight years later, this new generation preservative still holds full market share as the only alternative with environmental advantages over its predecessor solvent-based wood preservative products – namely TBTN, TBTO-L and PCP.

One of the popular features is the clear liquid preservation solution, which on application maintains the wood’s natural colour with a beautiful light honey shade. This makes it the logical choice for treating architectural features such as stairways, laminated beams, roof trusses, ceiling boards, flooring, panelling, doors, cupboards, skirting and window frames amongst others.

The preservative is applied in a pressure treatment vessel in a controlled environment and is used to treat primarily value-added sawn timber products such as laminated beams, timber cladding, flooring and ceiling. Vacsol Azure treated wood is used in above ground, internal hazard applications (H2), and when selectively used in H3 applications (wood out of ground contact, exposed to weathering and leaching) a superior quality water repellent needs to be used and maintained.

“The warmth and natural beauty of wood works wonders for designing sustainable architecture that creates a sense of balance and calm gives. The addition of Vacsol Azure wood preservative takes these designs to the next level by preserving its beauty for homeowners to enjoy for years to come,” said du Plessis.

 Tanalith solution for green landscaping

Tanalith E wood preservative was first formulated for use in European countries during the late 1990s as a more environmentally acceptable wood treatment. The new generation Tanalith E embraces the same eco-sensitive ethos of environmentally discerning landscapers and particularly gardeners who grow edible product in lined wooden planter boxes.

“The primary benefit of growing your own food is the knowledge that it is organic, which is why it makes perfect sense to use Tanalith E preservative,” added du Plessis.

Tanalised E pressure treated wood can be used in hazard classes H2 (interior), H3 (exterior), H4 (in ground contact) and H5 (in contact with fresh water) but not for marine applications. The H4 hazard classification covers wooden products such as landscaping sleepers, non-structural retaining walls, garden edges, fence posts and lined planter boxes. Tanalith E has been used internationally for many years and local applications include the restoration of Chapman’s Peak boardwalk and enclosures and walkways at the Johannesburg Zoo.

Table 1: Hazard Classes

Hazard class Exposure Biological hazard
H1 Inside, above ground Lyctid borers
H2 Inside, above ground Borers and termites
H3 Outside, above ground Moderate decay, borers and termites
H4 Outside, in-ground Severe decay, borers and termites
H5 Outside, in-ground contact with or in fresh water Very severe decay, borers and termites
H6 Marine waters Marine wood borers and decay


“Equally important is the need for green rated wood preservatives that contribute to the green building rate system.”