The sustainable lifecycle of a timber roof lantern: Accoya® - Westbury Windows and Joinery

The sustainable lifecycle of a timber roof lantern: Accoya®

You can install a beautiful new roof lantern into your home and help the environment at the same time by choosing a product made from renewable, eco-friendly materials. We look at Accoya, a revolutionary eco-friendly timber, and discover why it is sustainable at every stage of its lifecycle.

You do not have to spend your time at home living in dark and gloomy rooms. A roof lantern is a highly effective way of introducing natural light, space and style to your home, bathing your interiors with sunlight during the day. It can create the impression of an elevated ceiling, giving an otherwise ordinary space the wow-factor. 

Design is everything when it comes to these glazed masterpieces, and the proportions between width, height, depth of roof makeup and lantern pitch should all be well balanced for an impressive aesthetic. 

What material should you use for your roof lantern? 

With the continuous rise in population, our consumption of resources is consistently on the up. Despite awareness campaigns and desperate pleas for change from experts, we still have a mainstream throwaway culture. We continue to damage our beautiful planet with mass deforestation, poor waste management, plastic debris in our oceans and toxic emissions. 

We are using non-renewable manufactured materials like plastic, uPVC, concrete, and metal on a vast scale. Only a small percentage of these materials are ever recycled. When they are, the process just produces more emissions into the atmosphere. 

If this is the case, wood and timber must surely be a better choice. A traditional timber roof lantern is a remarkable sight, with its clean lines and balanced symmetry. Unlike other materials, you can achieve more exquisite detailing from timber, which gives the structure character and creates an incredible architectural impact. 

A sustainable alternative to hardwood

Unfortunately, there are not enough resources to harvest hardwood timber sustainably anymore. We are destroying our tropical rainforests at such a high rate, with 8 million hectares of tropical regions deforested between 2005 and 2010.

Through the photosynthesis process, trees absorb CO² and solar energy as they grow and create more wood. In turn, they release oxygen back into the air. According to the Centre of Life and Food Sciences at Weihenstephan Technische Universitat in Munchen, the denser the wood, the more carbon is stored, but on average 1M³ of wood can store over 1 ton of CO². We are quickly depleting our resources while releasing these carbon greenhouse gasses into the environment. 

The ideal material for a roof lantern is natural and environmentally friendly, and combines all the positive attributes of wood without the performance issues. You would think this would be a tall order, but this is where Accys Technologies in Holland steps in with their revolutionary product, Accoya®. It is CO² neutral throughout its full lifecycle, 100% biodegradable and offers exceptional performance. 

We use Accoya® for the outward-facing section of our engineered timber, and for particularly vulnerable elements of our projects such as the ridge cap of a roof lantern or the external window cill. We also use Tricoya® (a version of MDF made from Accoya®) to manufacture our door panels. 

What is engineered wood?

Engineered wood consists of layers of timber sections, which are compressed, bonded, and laminated together. The direction of the grain in each section alternates, making the layers stronger and more dimensionally stable than solid wood. 

The layers of wood are arranged so that the most durable and stable wood material is on the exposed side while the aesthetically pleasing grain is used on the inside.

Engineered timber also generates 25% less wastage than solid wood, where long sections of completely defect-free timber needs to be sourced. 

Lifecycle Stage 1: The Forest

Trees are essential for helping to keep our air fresh and clean – they filter CO² out of the air and absorb it in their biomass. Wood is renewable, and responsibly managed forests ensure that only the older, faster-growing trees are harvested and replaced while the younger trees are left to grow. Because of sustainable management in Europe and North America, their net forest area has been increasing steadily for several decades. 

Accoya® primarily comes from abundantly available, fast-growing tree species such as Radiata Pine, which is sustainably sourced from New Zealand, Chile or Spain. It takes approximately 28 years to harvest, compared to 70-120 years for a hardwood alternative. It is transported to the Accys Technologies plant in Holland where it goes through the acetylation process that transforms it into a wood that would challenge any hardwood. 

Accoya® wood is one of the very few building products to have acquired Cradle-to-Cradle certification at the stringent Gold level. Cradle-to-Cradle (C2C) provides a means to tangibly and credibly measure achievement in environmentally intelligent design including the use of environmentally safe and healthy materials and instituting strategies for social responsibility.

Lifecycle Stage 2: Production

Acetylation is a revolutionary wood modification process, which has taken over 80 years to develop. The wood particles react with acetic anhydride, through which the free –OH (hydroxyl) groups within the cell wall are replaced by more stable and hydrophobic non-toxic acetyl groups. 

As a result, the stability and durability of the wood significantly increase. The co-product of this process is acetic acid, otherwise known as vinegar in its dilute form, which is taken away to be reused in a wide range of industries. 

Lifecycle Phase 3: The Roof Lantern

The most sustainable materials are those that never have to be maintained, replaced or thrown away. While it seems like you are helping the environment by sourcing sustainable timber, poorly performing wood results in an unstable roof lantern with a short lifespan that requires replacing after 25 years. Materials such as metals, plastics and concretes may be more durable than most woods. Still, the environmental damage caused during their production and disposal counteracts any benefits. 

Through acetylation, these disadvantages of wood are overcome, resulting in an environmentally friendly and high performing building material that lasts. First, Accoya® and Tricoya® have achieved the most upper durability class possible (Class 1 – EN 350) and are guaranteed up to 50 years. The longer lifespan enables fewer replacements over the same period compared to most other materials, while having more substantial carbon sequestration benefits. Secondly, the superior dimensional stability of Accoya® and Tricoya® means fewer paint coatings are needed, further contributing to a lower environmental impact. Finally, compared to other durable wood species, Accoya®® offers superior thermal insulation, which yields energy conservation advantages in applications such as window frames. 

Lifecycle Phase 4: End of Life

Accoya® is a non-toxic product and therefore, it is fully biodegradable. As a result, Accoya® can be treated in the same manner as standard natural wood at the end of its life cycle. The most sustainable option is to give it a second life by upcycling into something new. If this is not possible, it can be used to produce Tricoya®, which is a modified wood fibre technology also developed by Accsys Technologies. Tricoya® is widely recognised as the gold standard for high-performance wood elements such as external door panels. 

If this is not an option either, discarded Accoya® can be used for green, clean energy production, as wood products are essentially stored solar energy. They simply release the same CO² absorbed during growth, rather than producing new emissions caused by burning oil, gas or coal. 

Our roof lanterns consist of engineered timber sections, which are paired with high-spec double-glazing and aluminium capping for a high-quality product that looks beautiful and is very low maintenance. For more information about our products, or to visit our workshop, please call us to arrange an appointment.