natural and manufactured timbers

softwood

• comes from a coniferous tree

• bears needles (leaves) and has cones (seeds)

• evergreen - usually keep their needles all year round, even in winter

• grows quickly - cheap and readily available

• used in construction industry

• examples: pine, larch, cedar

hardwood

• comes from deciduous trees

• broad-leafed variety - lose their leaves in winter

• produce seeds in fruits / nuts

• grows slowly - more expensive

• examples: oak, sycamore, beech

what are the 3 categories that timber-based materials can be separated into?

felling

term used for cutting down a tree

• traditionally done by hand using an axe / very long saw

• now: chainsaws - modern chainsaw attachments can fell a tree, de-branch it and cut it into equal length logs in one action

growth rings

once cut, we can see the cross section

has growth rings - show the age of the tree (each ring represents one year of growth)

hardwood cell structure

less porous and denser cell structure than softwoods - makes many varieties harder wearing and less prone to rotting

value of hardwoods?

• comes in a variety of colours

• has many sought-after aesthetic and physical properties

• caused much illegal felling of trees, especially in rainforest areas - large areas have already been cleared, negatively impacting the natural environment and wildlife habitats

ash (pale brown / cream)

• flexible

• tough + shock resistant

• laminates well

uses of ash

• sports equipment

• tool handles

beech (dense/close grain with an attractive pink hue)

• fine finish

• tough

• durable

uses of beech

• children’s toys and models

• furniture

• veneers

mahogany (rich reddish-brown)

• easily worked

• durable

• finishes well

uses of mahogany

• high end furniture and joinery

• veneers

oak (light brown with an interesting and variable grain)

• tough

• hard

• durable

• high quality finish possible

uses of oak

• flooring

• furniture

• railway sleepers

• veneers

balsa (pale cream / white - an open grained, large and unusually fast-growing hardwood tree)

• very soft and spongy

• very lightweight

• can snap in thin sections

uses of balsa

• prototyping and modelling - especially model aircraft

softwood cell structure

• more porous cell structure than hardwoods

• if unprotected, it can absorb moisture and begin to rot - cedar contains natural oils which protects it + makes it suitable for exterior roofing

softwood - colours?

• not available in as many colours as hardwood

• can easily be stained

• frequently coloured to look like more expensive hardwood

larch (pale to reddish brown with a contrasting grain)

• durable + tough

• good water resistance

• good surface finish

• machines well

• issues with loose knots

uses of larch

• exterior cladding

• flooring

• machined mouldings

• furniture

• joinery

pine (pale yellow to pale brown - attractive grain that darkens with age)

• lightweight

• easy to work

• can split and be resinous near knots

uses of pine

• interior construction (and exterior if treated)

• cheaper furniture

• decking

spruce (white/cream with fine even grain)

• easy to work

• high stiffness to weight ratio

• variable results when staining

uses of spruce

• construction

• furniture

• musical instruments

manufactured boards

• usually sheets of processed natural timber waste products or veneers combined with adhesives

• made from waste wood, low-grade timber & recycled timber

• can be covered with a veneer to give appearance of solid wood

veneers

• produced by taking thin slices of natural wood from the trunk of a tree

• then bonded to the surface of cheaper sheet materials, such as mdf or plywood

medium density fibreboard - mdf (smooth, dull, light brown finish available in many veneered options - edges can be hard to finish well)

• rigid and stable

• good value with a smooth, easy to finish surface

• very absorbent so not good in high humidity or damp areas

uses of mdf

• flat pack furniture

• toys

• kitchen units

• internal construction

plywood (alternating layers of natural grain veneers with outer material usually of higher quality for aesthetics)

• very stable in all directions due to alternate layering at 90° with outside layers running in the same direction

• thin flexible versions available (flexiply)

uses of plywood

• furniture

• shelving

• toys

• construction

• interior, exterior and marine grades available for greater water resistance

chipboard (pale grey/brown with no natural grain - frequently covered with a laminate such as melamine formaldehyde)

• good compressive strength

• not water resistant unless treated

• good value

• prone to chipping on edges and corners

uses of chipboard

• flooring

• low-end furniture

• kitchen units and worktops

fsc

• forest stewardship council

• an international non-profit organisation that promotes responsible management of the world’s forests