Building Materials Flashcards
Carpet
- Production of nylon fibre from crude oil is the largest source of EC for carpets.
- should use recycled nylon fibres
- carpet tiles are better as you are able to replace individual items easier rather than ripping out whole ‘broadloom’ carpet
Concrete
- mixture of portland cement (10-15%) and water (15-20%) mixed with aggregates (sand, gravel, crushed stone)
- Types: Rebar - reinforcing steel rods. In-situ - concrete slab cast on site, pre-cast: concrete slabs cast elsewhere (better for EC as it is controlled
- Main EC impact comes from composition of cement
Reducing EC involves using alternative to portland cement with supplementary cementitious materials: - GGBS - a cement substitute made from the by-product of blast furnaces used to make iron.
- Fly Ash: by product of coal fired power stations
- Limestone Fines:
*Silica Fume - although these replacements mean the concrete will need longer to cure
- Better to use normal weight concrete (C32/40) instead of lightweight as you’ll need less rebar
ABS (Acrylonitrile Butadiene Styrene)
Opaque thermoplastic
* Can be cooled and heated without degradation making them suitable for recycling as opposed to thermoset plastics which can only be heated once during injection molding
* used for pipes and fittings
Types of Refrigerants
- CFC - Chlorofluorocarbons R11- highest gwp (banned)
- HCFC - Hydrochlorofluorocarbons R22/407C (banned)
- HFC - hydrofluorocarbon - R410a, R134a, R32 (regulated)
- HFO - hydrofluro-olefins - R1234yf, R1234ze - GWP <1 Honeywell is main manufacturer, ucertainties to how flammable it is.
Cork spray render and cork insulation board
- Cork oak tree - outer bark is used without felling trees.
- used as flooring insulation sheets or surface finish.
- regularly harvested cork trees store 5 times more co2 than lose left untreated.
- cork boards only use cork granules so totally natural.
- Resistant to sea salts make them ideal for coastal houses.
- Cork spray (rendering) typically 80% cork granules and 20% water based paint.
- can be applied on wide range of materials: steel, aluminum, wood, brick, vinyl, shingles
Inorganic Mineral derived Insulation
- Stone/rockwool - spinning molten rock and minerals with recycled steel slag
- Glasswool - recycled glass, lime stone, soda ash, sand
- Glassfoam,
- Perlite - volcanic rock have high water content which helps create large air pockets making it an excellent insulator (air is a poor conductor)
- Vermiculite,
- Expanded clay
Organic Fossil Fuel Derived Insulation
* EPS - Expanded Polystyrene - styrene monomer fused together obtained from petroleum although product is 98% air. recyclable and reusable
** XPS **- Extruded Polystyrene - manufactured using extrusion - a process which results in a closed-cell structure - preventing water absorption - also made with HFC blowing agent
* PUR - Rigid polyurethane - thermoset foam made with a HFC blowing agent
** PIR **- Polyisocyanurate ‘improved version of PUR’ - thermoset - much less require to achieve same U value.
Organic Plants/Animal Derived Insulation
- Woodfibre - made from waste softwood. wood sequesters carbon during its growth, reusable, recyclable. layer needs to be quite thick to ahieve optimal thermal efficiency.
- Cork
- Cellulose - plant fiber used in wall and roof cavities - mainly recycled newsprint/denim - heavily treated - usually blown in to fill the cavity or sprayed onto wall with moisture added. treated with borate
- **Straw Bale **- Fusing straw into boards without adhesives
- Cotton - 85% recycled cotton/15% plastic fibres
- Sheep’s Wooll - treated with borate to resist pests, fire, and mold - comes in batts
Innovative Insulation
Aerogels - low density solid gel, excellent insulators 3% sillica 97% air - small amount needed to achieve same U value as other common insulators
VIP - vacuum insulated panels - wrapping rigid fumed silica core within a high barrier-air-evacuated-envelope
NIM - nano insulation materials
Textile Fibers
Recycled PET
Steel
- iron ore, coal and scrap steel are main raw materials to make steel
- Melting process of iron ore is most impactful step.
- Electric Arc Furnace is a lower EC option than Basic Oxygen Furnace which uses 90% coal energy
- EAF 75% less embodied carbon than BOF because most of inputs to BOF are mined, raw materials so recycled content is typically only 30%.
- EAF melts scrap iron and steel into new steel up to 100% recycled content
Explore use of castellated beams (reduces quantity of steel)
Hollow Structural Sections 2x as intensive as L beams
Materials should be bolted instead of welded
avoid galvanized steel when not necessary.
focus is really on reducing volume of material rather than smelting process, as availability of smelting facilities depend on location
Timber
Specify products from sustainbly sourced forests (forests that are correctly replanted)
* local sourcing
*
Alumnium
- Made by smelting bauxite or nepheline ore
- very lightweight and durable
- is very electricity intensive
- growing demand for aluminium exceeds usable scrap.
Used in facades, cladding, windows, panels, and partition walls. - Low carbon aluminium involves primary aluminium made with 100% renewable energy and using recycled scrap aluminium
Copper
