New research emanating from North America and Sweden has people wondering whether transparent timber could become a viable alternative to silicate glass in architecture.
Separate scientific developments from Sweden’s Royal Institute of Technology and from America’s University of Maryland demonstrate ways to transform timber into a transparent material that could be used as a substitute for glass windows and solar panels.
The researchers used slightly different methods to achieve transparency, but both came up with similar results. Both teams used a chemical soaking process to remove the lignin (the molecule which gives wood its brownish colour) from their timber samples before adding chemicals for strength or extra transparency. The Swedes used a polymer to increase the optical transparency of their veneer substrate sample while the Americans covered their linden wood in an epoxy for strength because their lignin extraction process already rendered their timber highly transparent.
Above: Sweden’s Royal Institute of Technology sample appears highly transparent by removing the lignin in the wood veneer. Photography by Peter Larsson
Below: The University of Maryland researchers report that their three-inch (7.6 cm) block of wood had high transparency and also high haze. Photography by Liangbing Hu
While the technology isn’t there yet, there are suggestions that it could eventually have a profound effect on the way we design buildings. The University of Maryland researchers found that transparent wood achieves better thermal insulation than glass while providing similar levels of light penetration, provides better light dispersion and is also is far stronger and less susceptible to shattering than silicate glass.
Problems so far include the size of the samples, their colour and the chemicals used in the process. Fourteen by fourteen centremetre wood blocks are the largest samples that have been transformed and coating the timber in a big hunk of epoxy makes the process less environmentally-friendly.
You also have to ask whether you want the glass on your building to have a yellow haze considering views out are such a valued commodity.
The next steps in process are to swap the epoxy with recycled plastic and scale up the process.
Images: New Atlas