Glossary Flashcards
Retrofit
modifying or repairing a building after its been manufactured to achieve higher thermal performance and energy efficiency
EnerPHit
Admission that a retrofit wont meet levels of energy efficiency as passivhouse standard of 85-90%. Sets a required performance lower than passivhouse.
KGCO2e
GHG emissions expressed in CO2e responsible for global warming. It is a metric measure that is used to compare emissions from various greenhouse gases on the basis of their GWP by converting amounts of other gases to the equivalent amount of CO2. methane = 25 nitrous oxide = 298 (1 kg of methane = 25kgco2e) (IPCC 2007)
GHG
A greenhouse gas, therefore, is a gas that absorbs and emits radiant energy at specific wavelengths within the spectrum of infrared radiation emitted by the earths surface, thus causing the so-called greenhouse effect on Earth
GWP
GWP indicates the amount of warming a gas of a given unit mass causes over a given period of time relative to that of carbon dioxide, which is normally 100 years
Embodied Carbon
Emissions associated with materials and construction processes throughout the whole life cycle of an asset.
It includes any CO₂ created during the raw material extraction, transport to manufacturer, manufacturing the transport of those materials to the job site, and the construction practices used.
Put simply, embodied carbon is the carbon footprint of a building or infrastructure project before it becomes operational. It also refers to the CO₂ produced maintaining the building and eventually demolishing it, transporting the waste, and recycling it.
contributes to approximately 11% of global CO2
Embodied Carbon stages
(A,B1-B5,C)
A1- Material Extraction
A2 - Transport to factory
A3 - Manufacturing
A4 - Transport to site
A5 - Construction
B1 - Use
B2 - Maintenance
B3 - Repair
B4 - Replacement
B5 - Refurbishment
C1 - Deconstruction
C2 - Transport
C3 - Waste Processing
C4 - Disposal
D - Reuse, Recovery, Recycling
not included B6,B7 - Operational.
Whole Life Carbon
Sum of Embodied and Operational
Design principles for structure
Weight - the leaner the better
Grid - large grid spans will mean deeper beams and lower ceiling height increasing EC
Slab - slabs biggest impact for low-mid ride buildings. many variations of slabs which tend to rely on concrete
Column & Beam - higher ceilings = heavier beams (more EC), columns usually a hotspot
Foundation - lighter the building, smaller the foundation. typically 2nd or 3rd most impactful
Design principles for facades and interiors
Envelope - insulation
Facade - reduce metal use, high quality windows, limited shelf angles
Interiors -
space for maintenance,
reduce quantity of metal studs and frames,
use of recycled or up cycled furniture, Replace HFC blowing agents (foam up to form insulation) with HFO blowing agents. HFO is used as a blowing agent to form polyurethane foam (very low GWP)
Design principles for MEP
Passivehouse - Optimise MEP equipment e.g natural ventilation and shading devices to reduce over reliance on building service equipment
Refrigerant - Reduce the charge of refrigerant needed, e.g Hybrid VRF (part water/part refrigerant instead of standard VRF
Use low GWP refrigerant (<150),
ensure low leakage rates during system use,
refrigerant recovery at end of life
Optimisation
Use efficient equipment while specifying lowest weight possible
Minimise length of pipes and ducts
Specification
Specify robust equipment which wont be replaced often
ensure equipment are easily accessible for maintenance purposes
Circular Economy
materials can be retained in use at their highest value for as long as possible and are then reused or recycled, leaving a minimum residual waste
Carbon assessment
an LCA that only looks at one environmental impact indicator: Global warming potential (GWP), measured in CO2e
EPD
Independently verified and registered document that communicates transparent and comparable information about the life cycle environmental impact of a product
EN15804 + A2
Defines how companies should go about creating EPDs. Makes sure EPDs in construction sector are transparent and comparable.
- Accounts for end of life recycling (D)
- Includes more life stages
- biogenic carbon reporting
- reporting on additional environmental impact indicators
- detailed descriptions of functional units
ISO 14025
Sets out overarching procedures and requirements for producing EPDs
Refrigerants
A chemical used in a cooling mechanism, used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition liquid to gas and back again. They all work by passing a refrigerant between main components of the compressor, condensor, expansion device and evaporator to remove unwanted heat from one location (office to air). a refrigerant means that a fluid can easily boil into a vapour and also condensed from a vapour back into liquid again and again without fail.
Heat production options
Traditional district heating - development boilers & CHP, wider area heat network, hybrid systems
low grade district heating - centralized heat pumps or fuel cell
ambient loop - decentralized heat network - local heat pumps in apartment
local heat source - heat pump, boiler
Cladding
Non structural external layer mainly for appearance not so much for insulation but used to protect from the elements. generally requires attachment to battens/backing wall (CLT)
recycled polystyrene
Timber
Stone
Vinyl
Glass
Brick
Cement Fiber Board
Metal
External Foam
Galvanizing process
Coating steel with zinc
Biogenic carbon
carbon stored in biological materials such as plants or soil. Refers to the carbon removals associated with carbon sequestration into biomass. bio-based products can contribute to reduce levels of co2. Biogenic must be reported separately if reporting only in upfront carbon but included in total if reporting EC or WLC
Wall rendering
covering exterior wall surface either with a sand and cement, lime based, or synthetic resin based render to give the house protection against weather
Facade
The principal front of a building that faces onto a street
high rise buildings often have curtain walls (non load bearing to keep weather out) /precast concrete walls which are suspended from concrete floor slabs.
Rooftop Units
most common HVAC system for commercial buildings. uses refrigerants - warm air from building passes over evaporator coil and refrigerant extracts heat from the air by absorption
VRF - Variable Refrigerant flow
a core HVAC indoor or outdoor system, allows single compressor to serve multiple indoor units
AHU - Air handling units
Composition of elements mounted in large accessible box-shaped units called modules which house the appropriate ventilation requirements for purifying, air conditioning or renewing the indoor air in a building.
Walls
Load bearing wall - carries load imposed on it from beams and slab. precast concrete wall, retaining wall, masonry wall
Non load bearing wall or interior walls don’t support structure just used to seperate rooms from outside
Cavity walls - cavity between two walls, prevent rain penetrating internal surface
Partition wall - interior non-load bearing wall divides large space into smaller spaces
Masonry wall: brick
Shell and core
Shell is structural element that divides inner space of structure from the structure’s outside. Core -
LCA
A science based method of assessing the potential environmental impacts associated with a product throughout its life cycle.
Performing Building LCAs
Defining goal and scope definition
System boundaries - life cycle stages and building area (GIFA) - Service life of building
Life cycle inventory
Life cycle analysis
Standards
ISO 14040/4 - Fundamental for LCA -Goal and scope, LCI, LCIA, Results and limitations
EN15978 - European standard specifies calc method based on LCA to assess env performance of a building
EN15804 - Standard for making 3 different types of EPDs, cradle to gate,grave,gate with options
GLA - How to calc WLC emissions in line with London plan 2021
Damp proof membrane
Ideal for applications like flooring. For walls, need to make sure the membrane is breathable
Operational Carbon
Greenhouse gas emissions associated with energy and water use during a building lifetime
Upfront Carbon
Cradle to practical completion (A1-A5) - excluding biogenic carbon
Carbon Sequestration
Process by which co2 is removed from the atmosphere and stored within a material e.g stored as biogenic carbon in ‘biomass’ by plants/trees through photosynthesis and other processes
Biomass
material of biological origin excluding material embedded in geological/fossilized formations
Carbon Offsets
Emissions reductions or removals achieved by one entity and can be used to compensate from another entity
- offsets must be verified and retired in line with GHG protocol
- carbon emissions must be minimized before offsetting
- offsets should be purchased in advance
- exported renewable energy generated cannot be used to account for EC
Types of EPDs
Generic EPDs - averages between number of manufactures for same product
Manufacturer specific EPDs - range of specific products from same manufacturer
Product specific EPDs - product specific from manufacturer
