Here is our ‘master list’ of various key sustainable building materials and methods. A short definition and key features have been given as well as a number of links to good external sites for you to learn more.
Core structural materials and methods:
Similar to Cob. Sand, clay, water and some kind of fibre like straw or sticks. Bricks shaped with frames and are left to dry in the sun. Also see Superadobe, a combination of this and earthbag construction, that, believe it or not, was developed by NASA.
AKA – boooooring. 😉 However, this is probably the most familiar method (in the West at least), and reclaiming bricks from demolition can be a good alternative to making new ones. As Father Jack puts it, “I LOVE MY BRICK”
[the brick development agency]
Imagine trying to make a brick wall out of chopped logs, where the gaps are filled with mortar, cob or similar. Sometimes referred to as ‘stackwall’ or ‘stovewood’.
Generally characterised by tire walls filled with earth, and large windows to maximise solar gain (aka heat from the sun). Rammed earth tires (while fairly hard work to make) are extremely tough, good insulators and largely fireproof. Other materials may include tin cans for internal walls and glass bottles for ‘window-esque’ features.
Very much like a sandbag, except… well, you get the idea. Plastic or natural bags filled with clay soil or gravel, a straightforward construction method similar to bricklaying. Finishing in plaster or similar is required to be waterproof.
Insulated Concrete Form (ICF)
Imagine hollow LEGO bricks that are subsequently filled up with insulation. Lower skills and less time required to construct, however their overall sustainability really depends on what you make and insulate or fill them with. Expanded polystyrene (EPS) may also be used for the forms, considerably lighter!
Modular / Pre-fab / Flat-pack
A modern method by which as much of the construction is completed in an off-site facility as possible before being transported to the site. (compared to a ‘site built’ or ‘stick built’ process)
Rammed earth / Compressed earth block
Generally a frame is used to create forms in which earth (of a suitable moisture and clay content) is compressed by hand or machine.
[wikipedia – rammed earth]
[wikipedia – compressed earth block]
Roundwood / Roundhouse / Reciprocal frames
Typically ’round’ in terms of building surface area and ’round’ in terms of the timber used; that is, timbers that are not milled into rectangular shapes. A reciprocal frame creates a roof structure that, with careful balancing, requires no central support and thereby maximises floor space. Technically these are all still ‘timber-frame’, but different enough to warrant some clarification!
[wikipedia – roundhouse]
[wikipedia – reciprocal frames]
Structural Insulated Panels (SIPS)
A pre-made ‘sandwich’ of panel (timber, metal, cement) and filler (polystyrene or other foam) likely to be used as part of a ‘flat pack house’ style of construction. Potentially very fast to build and the uniform panels can be used not only for walls but floors and ceilings too.
Standardised, steel, sturdy and shrewd (?), these steel boxes are available relatively cheaply around the world. Not inherently well insulated or familiar to planning departments unfortunately, they may also require some serious decontamination depending on their previous cargo.
A sturdy and cheap agricultural waste product. The key downsides are susceptibility to damp and rot, though decent foundations and finishing can solve these problems. Also as ‘bricks’ they are quite large, though this is what provides good insulation properties.
Additional, generally non-structural materials and methods
Plaster and Stucco
What’s the difference? At a basic level, very little; they are both some combination of aggregates, binders and water that is used to cover a surface, may or may not be weatherproof, and are principally used as finishing, rather than load-bearing building materials.
[wikipedia – plaster]
[wikipedia – stucc0]
Similar to Plaster and Stucco, in theory can be used for finishing, but principally for binding brickwork together. Lime mortar was the more typical choice in brickwork until roughly the 19th century, when cement became the ‘binder’ of choice.
[wikipedia – mortar]
[wikipedia – lime mortar]
A mixture of plant fibres and lime, sand or cement to create solid concrete-esque blocks. It is less brittle than concrete, which has some advantages, however it is substantially less tough in regards of compressive strength and is not typically used as load-bearing.
Tin can walls
Food (tinplated steel) or drink cans (mainly aluminium) can be laid in horizontal or vertical rows and joined together in a similar way to conventional brickwork. Not great load bearing properties, but decent insulators, recycled and potentially very cheap.
[wikipedia – tin can wall]
Bottles (or other uniform glass vessels) laid horizontally and joined as with conventional brickwork. Not great for load bearing, but potentially a very attractive in their own right with a variety of colours to use. Also weatherproof.
[wikipedia – bottle wall]
Wattle & daub
More modern version being lath & plaster (even more modern being plasterboard). Panels are weaved from branches, then covered in ‘daub’, the exact ingredients of which are pretty variable. ‘Laths’ are small strips of wood that are nailed across wall studs then covered in plaster.
[wikipedia – wattle and daub]
[wikipedia – lath and plaster]
Generally referring to a specific style of timber building, though a range of shed or garden cabin type buildings are often called log cabins.
‘The most common roofing material in the world’ due to the ubiquity of the grasses or leaves required to build it. While it is simple and light, a variety of problems such as price, percieved fire risk and general ‘wildlife interference’ should be taken into account.
Are we missing something? Let us know.