Building From Trees

Trees are the biggest plants on our planet, they give us oxygen, store carbon, stabilise the soil and provide a home to the world’s wildlife. They are a renewable resource and can be very sustainable when managed correctly. This research looks at how the construction industry can make use of materials derived from trees.

Cork

Cork is a high performance, natural, sustainable and vapour permeable material for use internally and externally. It is 100% recyclable and has very low embodied energy. Cork also has excellent acoustic qualities. Cork is an extremely clean material which does not emit any toxic fumes. It is resistant to damp and rot and is unattractive to mice and termites.

Cork originates from the bark of the cork oak tree which is common in Southern Europe and North Africa.

Cork insulation is made from natural cork which is removed from a tree about every 9 years after the cork tree has grown for about 25 to 30 years. The tree is not harmed in this process and does not need to be cut down. The cork bark grows back over time.

The processing of cork is relatively low energy and does not require chemicals or artificial binders. The cork is cut from the tree and then left to rest for about a year. It is then boiled and left to dry out. It is then ground down into cork granules which are then pressed under high pressure and steam to make the boards. The cork creates a natural binder in this process which forms the board.

Cork is commonly used for insulation in ceilings, floors, and walls of buildings. However, it has also become common in-home interiors, as it provides a natural element of design. Cork can also be used to make tiles or blocks which can be used as the sole construction material of a building.

Cork insulation can be applied in many different forms: As insulation boards, as loose granules which may be suitable where access is restricted. It can also be mixed with a hydraulic lime binder to form a render/plaster that can be applied internally or externally.

Rubber

Rubber is highly elastic, durable and corrosion resistant material that stays flexible in a wide range of temperatures. It is also water resistant and an electrical and thermal insulator. Rubber is commonly used in the construction industry for joints, seals, flooring and gaskets.

Rubber is obtained almost exclusively from Hevea Brasiliensis, a tree indigenous to South America. It was originally created from the latex sap of the trees, a generally naturally strong elastic substance. Some companies have introduced mineral fillers, natural pigments and vulcanization accelerators to the rubber production process allowing the material to be produced in a variety of bright colours.

Rubber has been largely used as flooring and is often recommended for public and high traffic buildings, as the material is easy to clean, has anti-slip properties and can absorb movement and vibrations.

Timber (internal finishes)

Timber is a versatile raw material; it is a renewable resource and is grown in countries around the globe. This reduces the amount of transportation needed, allowing the material to be used closer to where it is produced. Timber has a fast growth rate with softwood varieties able to replenish at a faster rate than hardwoods. It is easy to harvest and can be managed effectively to assure regrowth and replenishment, making it a very sustainable material.

Timber is a high-performance material for flooring and other architectural finishes. It is durable and low maintenance. Timber finishes can help to improve indoor air quality by moderating humidity levels.

Timber (shingles)

Timber Shingles are thin, ergonomic, and easy to install. As a material they have a life expectancy of about 50 years depending on the tree species used. They are low maintenance, breathable and hold a low carbon footprint. They also look great.

Timber (structure)

Timber has been used for thousands of years around the world as a structural building element. Here are some of the ways timber structure is used today in architecture.

Timber framed construction uses external and internal stud walls, floor joists and roof trusses to form a complete structural frame that transfers the vertical and horizontal loads to the foundations.

Timber framed construction has a quick build time and has a low volume of waste on site requiring removal.

Timber post and beam construction is a building method that comprises vertical structural posts and horizontal beams, jointed to form a structural frame into which walls are placed.

Cross Laminated Timber (CLT) is a product where timber lumbers are glued together. Layers are orientated perpendicular to each other to create structural timber panels.

Glued Laminated Timber (Glulam) is similar to CLT but the layers of lumber are oriented in the same direction when glued together. They are usually formed to create strong columns, beams or arches in structures and are usually held together with steel bolts, dowels and plates.

Palm Thatch

Coconut Palm (Cocos nucifera) leaves are the most widely available thatching material in the humid tropics. Hundreds of millions of people rely on them for their homes and businesses. An average tree produces up to 40 leaves every year. The leaf comprises up to 200 leaf blades which grow, at an angle, to the leaf stem.

The maintenance of these roofs is minimal, however it is combustible, so chemicals must be used to make the roof completely fireproof. Palm leaves are renewable, and comfortable in warmer climates.

Coir Fibre

Coir Fibre is extracted from the outer husk of coconuts which are harvested from the Cocos nucifera palm tree.

Coir fibre is emerging as a construction material used in concrete mixes. Coir fibre-reinforced concrete can be stronger than concrete without coir fibre. Since coir fibre is not as dense as concrete it reduces the overall weight of a structure, making it ideal for producing a lightweight form of concrete. Being a renewable resource, it is generally more sustainable than artificial fibres.

Cardboard

Cardboard has become more attractive to architects because it is low-cost, 100% recyclable and an environmentally sustainable option, but also because it has the mechanical properties required to withstand heavy loads.

Twigs

Twigs are flexible and can bend easily to form different shapes. Twig-work is the term applied to architectural details constructed of twigs and branches to form decorative motifs in buildings and furniture. Joinery on twigs and branches are like joinery for lumber. Mortise and tenon joints are strong but they can also be fastened with nails. Where one branch meets another the ends must be coped or cut to match the curve.

Coconut Shells

Coconut Shells are a material that have been used for many years in the vernacular architecture of tropical regions where they grow.

When building structures, the shells are first collected, seasoned and sun dried for about 7-8 days to make them become hard. They can be used to create walls, that can then be plastered with mud. The shells are natural air coolers due to their air cavities.