Let's start at the beginning: what exactly is plywood?

Plywood is a manufactured board that is made from layers of solid timber veneer (or plies). The rotary cut veneers are normally cross layered, glued together and compressed under heat. Because it is made in layers it is incredibly strong but also light in weight.

Plywood can also be moulded into single or double curved shapes. This is done by aligning the veneers on a curved base. During the pressing process, glue then bonds the veneers into the desired shape.

In Europe, beech and birch wood are preferably used for moulded plywood because of its availability and high bending strength.

Modern history of plywood

The breakthrough for the plywood industry was the invention of the rotary cutter in the 19th century, which allowed wafer-thin sheets of timber to be shaved off a log. (Heathcote, 2017)

After being highly developed in the war’s aircraft industry, plywood also started to become a commonplace material of domestic life after the second world war. Across this period plywood’s standardised production around the world and its unique material properties enabled its use on a much larger scale than ever before. (Wilk and Bisley, 2017, p.148)

Factory manufacture reduced the production costs of plywood chairs, which made them for the first time affordable for a major part of the population. When plywood was introduced to the furniture market, its ability to be moulded inspired various modernist architects in the first half of the 20th century, to reinvent the traditional shapes of seating.

Changes in function and design

Opposite to bentwood, which was invented a decade earlier by Michael Thonet, and allowed the bending of wooden dowels, plywood, for the first time, enabled the creation of curved surfaces for seats. One revolutionary opportunity was to form single-piece plywood seats and backs for chairs, which was first explored by Gerrit Rietveld and Alvar Aalto around 1930.

During the postwar years Ray and Charles Eames, together with the Finnish-American architect Eero Saarinen brought groundbreaking changes when experimenting with moulding plywood in more than one plane.

“Their goal was to produce functional and cost- efficient chairs that would perfectly adapt to the human anatomy. Although their early designs did not allow for complex curves that could be comfortable without upholstery, after five years of experimenting they found a way to both bend and mould plywood, creating compound curves that were optimal for the human body.” (MoMA Learning, no date) Their DCM chair became the most influential and imitated chair of the mid-twentieth century. (Wilk and Bisley, 2017, p.160)

Features of spring

Wood is an elastic material. Due to its fibrous structure it is able to bend and twists. Therefore every piece of plywood, which is a composition of whin wooden layers, naturally has a sprung feature. Depending on the material thickness, surface outline and the supporting chair base, elastic effects in seat and backrest can be created. Following designers explored these characteristics and used them in chair design.

Aalto’s Paimio chair embodies a sprung seat, floating between its supports. The cantilevered chair enables an elastic movement of the whole seat supported by a frame in the shape of an open curve.

Various designers in the 1950’s played with the flexibility features in the backrest. By cutting holes or tapering parts of the chair shape, a “mobile joint” could be created.

In Sori Yanagi’s Butterfly stool it is the projecting surfaces of the seat that create a slight sprung effect.

Latest innovations

About 40 years had to go by till the use of plywood for furniture was innovated.

“1992 Frank Gehry, inspired by woven baskets, created the bentwood furniture collection” for Knoll. (Architectural Record, 1992)

The novelty of his designs was any waiver of additional materials. The continuous and fluid structures of the chairs are exclusively made out of lightweight plywood strips, which, at the same time create a springlike comfort. The items are sold within a price range from 1100 - 7200 £. 

Looking at the 21st century we find rather insignificant developments in the field of moulded plywood.

As an evolution of the Gehry chairs, german designer Jens Otten developed a flexible lightweight chair in 2008 using CNC technology. 

One of the probably most outstanding concepts in the last years is a stool made by Chinese designer Min Chen, which is a stack of bamboo layers, bent into an arc shape. The airy arrangement of bamboo veneers, glued together at the ends to form the legs, creates not only a unique look but also a new sitting experience. Nominated for the Loewe Craft prize in 2018, the stool gained reputation but is not on the market yet. 

Literature

Heathcote (2017) ‘How plywood took off as a design material’, 13 July. 

Wilk, C. and Bisley, E. (2017) Plywood: a material story. [London] : London: Thames and Hudson ; V&A. 

MoMA Learning (no date) Side Chair (model DCW). 

Architectural Record (1992) Knoll Designer Bios - Frank Gehry.