Why Does Timber Turn Grey?
Timber can develop its distinctive grey colour in just a matter of months, particularly in areas with high rainfall.
This colour change occurs when sunlight breaks down the lignin in wood through oxidation.
This natural ageing process, known as patina, varies greatly depending on wall orientation and local conditions.
Due to direct sunlight, north—and west-facing walls weather faster, while east—and south-facing surfaces retain their original colour longer.
Though weathered timber might look aged, the grey surface layer acts as a shield, protecting the wood from further UV damage.
Architects prize this natural ageing characteristic as it creates a seamless connection between buildings and their surroundings.
The Science Behind Wood Greying
Wood’s journey from its natural colour to a silvery-grey patina involves fascinating chemical reactions at the molecular level. The process starts the moment timber meets sunlight and weather.
Weathering
The grey colour develops when UV rays interact with lignin, the natural compound that binds wood fibres together. UV light breaks down the lignin molecules through photochemical degradation. Rain then washes away these broken-down components, revealing lighter-coloured cellulose fibres underneath.
This weathering typically affects the timber’s surface layer, reaching depths between 0.05 and 2.5mm. The speed of colour change depends on UV exposure levels and local weather patterns. Due to harsh environmental conditions, coastal properties often see complete grey patina development within months.
Oxidation
Timber oxidation occurs when sunlight, moisture, and oxygen interact on the wood’s surface to create chemical changes. The process begins when UV exposure creates free radicals in the timber through photochemical oxidation.
The greying process follows four key steps:
– UV rays break down lignin and wood extractives
– These elements absorb sunlight, creating oxidants
– Oxidants trigger more chemical reactions
– The timber develops yellow-brown tones
Light-coloured timbers like pine show more obvious yellowing early in the process. On the other hand, darker timbers fade to pale brown before achieving their final grey patina. Heat and moisture can speed up these chemical changes. When UV rays combine with water, timber ages and weathers more rapidly.
Different Types of Wood Patina
The natural ageing process highlights timber’s inherent beauty, with each species developing distinct patterns through its exposure to the environment:
– Australian hardwoods like walnut develop a shift to lighter shades with honey-golden undertones.
– Cherry timber starts with lighter tones before developing rich, reddish hues, typically achieving its signature amber colour within 6-8 months.
– Maple timber begins with bright tones and delicate pink and grey undertones, maple matures into a rich golden patina.
– White oak shifts towards golden tones, while red oak develops deeper, warmer colours.
Embracing the Grey: Design Applications
Architectural Uses
Modern Australian buildings often feature grey timber cladding as their signature exterior finish. The material shines particularly well in coastal and bushland settings, where its weathered character mirrors the natural environment.
Grey timber elements flow beautifully from outside to inside, linking spaces through flooring, beams, and feature walls. Architects can create stunning visual depth by matching grey timber with contrasting materials and textures.
Interior Design Trends
Grey timber is making its mark in contemporary Australian interiors. Its versatile foundation for serene spaces and soft, natural tones, provides a calming backdrop that complements modern designs.
Interior designers are embracing the interplay between steely grey timber and warm wooden accents to create balanced, sophisticated environments. Whether used for statement walls or sleek flooring, grey timber adds understated elegance and a timeless appeal to any space.
Modinex’s Range of Timber Species
The process of timber patina and greying is a natural part of the timber lifecycle. While some may prefer the initial appearance of freshly cut or treated wood, others appreciate the character and low maintenance of weathered timber in outdoor settings.
Interested in patina timber or need ideas for your next project? Contact us today or explore our timber species range here.
Article By Charlton Cooper
| 18 July 2024
Charlton Cooper
Head of Projects
Charlton is a seasoned advisor in construction and design, collaborating with builders, developers, and architects to deliver exceptional projects. With extensive experience as a head of projects, Charlton combines deep knowledge of natural timber, aluminium, and concrete to provide innovative and inspiring design solutions.
