LCA Graphics and Construction Studies flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

First-angle projection layout

In first-angle orthographic projection the object sits between viewer and plane, so the plan is drawn below the front elevation and the end view appears on the opposite side to the viewer.

Scale ratio meaning

A scale of 1:20 means one unit on the drawing represents twenty units in reality, so a 75 mm drawn dimension represents 1500 mm on site.

Hidden detail line

A dashed line of medium thickness is used to show edges that are concealed in a particular view, such as a lintel buried inside a wall.

Section hatching convention

Cut solid material is hatched with evenly spaced 45-degree lines; adjacent components are hatched in opposing directions so joints and separate materials remain readable.

Site plan purpose

A site plan locates the building within its plot, showing boundaries, levels, drainage, access and north point, usually drawn between 1:200 and 1:1250.

U-value definition

The U-value is the thermal transmittance of a construction in watts per square metre per kelvin; a lower value means better insulation performance.

Thermal conductivity lambda

Thermal conductivity, symbol lambda, measures heat flow through a material in W/mK; lower values indicate better insulating ability for a given thickness.

Timber anisotropy

Timber behaves differently along and across the grain; it is much stronger along the grain and shrinks more across it, causing movement and distortion.

Concrete curing strength

Concrete develops strength through hydration over time; characteristic cube strength is normally specified at 28 days, and the water-cement ratio strongly affects it.

Vapour control layer

A vapour control layer is a low-permeability membrane placed on the warm side of insulation to limit moisture diffusion into the construction and reduce condensation risk.

Strip foundation use

Strip foundations are continuous concrete strips under load-bearing walls, suitable for firm subsoil where loads are relatively uniform along the wall line.

Raft foundation function

A raft foundation is a reinforced slab covering the whole footprint, spreading building load over weak or variable ground and reducing differential settlement.

Wall tie spacing

Wall ties connect the two leaves of a cavity wall; spacing is set by the masonry type and exposure, with closer spacing around openings and at edges.

Damp-proof course position

The damp-proof course is a continuous impervious layer in the wall, normally at least 150 mm above external ground level, preventing rising moisture reaching internal finishes.

Lintel end bearing

A lintel must bear onto masonry each side of an opening by a minimum distance, commonly 100 to 150 mm, so load transfers safely into the wall.

Roof pitch constraint

Minimum roof pitch depends on the covering: plain tiles need roughly 35 degrees, interlocking tiles less, and sealed sheet or membrane systems can be much flatter.

Fabric heat loss formula

Fabric heat loss equals area multiplied by U-value multiplied by the temperature difference across the construction, summed across all elements of the building envelope.

Air permeability units

Air permeability is measured in cubic metres per hour per square metre of envelope at 50 pascals, quantifying uncontrolled infiltration through the building fabric.

Stack effect ventilation

Warm air inside a building is buoyant and rises, drawing fresh air in at low level and exhausting stale air at high level; the driving force increases with height.

Condensing boiler efficiency

A condensing boiler recovers latent heat from flue gases when return water is cool enough to condense, so low return temperatures give higher measured efficiency.

Daylight factor definition

Daylight factor is internal illuminance at a point divided by simultaneous external horizontal illuminance under a standard overcast sky, expressed as a percentage.

Impact sound transmission

Impact sound is structure-borne noise such as footfall; a resilient layer beneath a floor screed or a floating floor reduces transmission into separating structures.

Work at height hierarchy

The hierarchy requires avoiding work at height where possible, then preventing falls using collective measures, then mitigating residual risk with personal fall protection.

Excavation support trigger

Excavations deeper than about 1.2 m generally need support or safe battering, and all excavations must be inspected by a competent person at each shift start.

Underground service location

Services must be located using utility plans plus a cable avoidance tool and careful hand digging, treating plans as indicative rather than proof of position.

Site welfare requirements

Site welfare must include drinking water, washing facilities, sanitary conveniences, rest area and changing facilities, provided from the first day of work.

Design constraint categories

Design constraints divide into statutory, physical, economic and user categories; a proposal must satisfy all four or it fails at planning, engineering or use stage.

Passive design hierarchy

Reduce demand first through form, orientation and fabric, then improve system efficiency, then supply remaining energy from renewables to meet the residual load.

Design decision matrix

A decision matrix scores design options against weighted criteria such as cost, carbon, buildability and maintenance, making trade-offs explicit and the choice auditable.

Whole-life carbon

Whole-life carbon is the sum of embodied carbon in materials, construction and replacement plus operational carbon over the building life, including end-of-life.

Coursework evidence types

Primary evidence includes measurements, tests and site photographs; secondary evidence comes from published sources and must be cited so claims can be verified.

Practical risk assessment

A risk assessment records the hazard, who may be harmed, existing controls, likelihood and severity, and residual risk, and must be completed before practical work starts.