Construction Technology & Environmental Services Level 1 Flashcards
Which RIBA stage is on-site construction?
RIBA Stage 5 - Manufacturing & Construction
What is buildability?
- the extent to which the design of a building facilitates the ease of construction
- to help improve buildability, early contractor involvement should be considered to benefit from their experience & expertise
What is the difference between building works & civil engineering works?
- Building works: all types of buildings such as houses, offices, shops, hotels, hospitals
- Civil engineering works: drainage schemes, highways, culverts etc
What are temporary works?
The parts of a construction project that are needed to enable the permanent walls to be built, they are usually required for safety & access reasons. Such as:
- propping
- scaffolding
- formwork
- excavation support
- access & task lighting
What are hoists?
Designed for the vertical transportation of materials and / or people
What is shoring?
- a form of temporary support given to existing buildings & excavations
- the purpose is to prevent collapse or excessive movement
What is a culvert?
- a tunnel-like structure that is constructed to allow water flow under a road, railway line or similar obstruction
What is the purpose of a drainage headwall?
- It’s a small retaining wall / structure built at the inlet or outfall of a storm water drainage pipe
- Used to protect the end of the drain as well as protect the watercourse embankment from erosion
What is the sub-structure of a building?
- the lower portion of the building in the ground which supports the superstructure
- transmits the loads of the building to the ground
- includes foundations, basements & retaining walls
What is ground heave?
- usually associated with clay soil, which swells when wet causing the upward movement of the ground
- as the soil cannot expand downwards or sideways, the result is the exposed upper surface of the soil rises up
What are the different forms of excavation?
- site clearance operations (removing vegetation & rubble)
- stripping topsoil
- reduced level dig (to reach formation level)
- cut and fill
- excavation for foundations
What are SUDs?
- sustainable drainage systems
- design to manage storm water as close to the source as possible to mimic natural drainage & encourage its infiltration
- help to reduce the reliance on existing drainage infrastructure
What is the purpose of a foundation?
- provide support for structures, transferring their load to the ground to avoid excessive settlement
- bear the loads of the superstructure
What are the typical considerations when selecting the type & size of foundations?
- total load of the building
- nature & load bearing capacity of the ground
- type of structure
- cost
- construction constraints (e.g. proximity to adjacent buildings / structures)
What is a raft foundation?
- essentially a continuous slab that extends over the entire footprint of the building
- spreads the load of the building over a larger area than other foundations, the stress acting on the ground below is reduced
- used when ground bearing capacity is poor
What is a pad foundation?
- Typically used in framed buildings to support perimeter or interior columns, spreading the load to the ground below
- usually square or rectangular on plan & can be reinforced or non-reinforced
- commonly used for steel & concrete frames, supporting commercial & industrial properties
What are strip foundations?
- a strip of linear structure that serves to spread the weight across the total area of the ground
- typically used on traditional residential construction
- can have shallow strip or deep strip foundations
What is the difference between shallow strip & deep strip foundations?
Shallow strip
- easier to construct so less labour needed
- possibility of settlement as they have a low resistance to lateral loads
Deep strip
- work at a greater depth, providing lateral support & resisting uplift
- more expensive as its a complex construction procedure which requires skilled labour
What are pile foundations?
- a column which extends deep into the ground
- used where the bearing capacity of the soil is poor or imposed loads are very heavy
- there are 2 main types of pile: end bearing piles & friction piles
- there are 2 main construction methods: bored piles & driven piles
What is the difference between end bearing piles & friction piles?
- End bearing piles: the bottom of the pile rests on a layer of strong soil or rock, the strong layer takes the load
- Friction piles - develop most of the pile-bearing by the shear stresses along the sides of the pile. So, the surface pile works to transfer the forces to the soil
What is the difference between bored & driven piles?
- fundamental difference lies in their point of manufacture
- a driven pile is formed off site under factory-controlled conditions
- bored pile is manufactured on site
What are the advantages & disadvantages of driven piles?
Advantages
- Can be precast to required specifications
- piles of any size, length & shape can be made in advance
- a pile driven into granular soil compacts the adjacent soil mass, the bearing capacity of the pile may increase as a result
- fast, neat & clean installation
Disadvantages
- requires heavy equipment for handling & delivery
- increased noise & vibrations generated by driving the piles
- can be costly if piles are too short
What are the advantages & disadvantages of bored piles?
Advantages:
- any size or shape of pile can be formed on site
- no risk of damage during delivery & handling
- reduced vibrations & noise
Disadvantages
- significant spoils are generated that need to be handled
- reliance & coordination on multiple trades
- do not improve bearing capacity of the ground
What are secant pile walls?
- a wall formed by installing interlocking piles which create a solid barrier free of gaps
- typically used to form a retaining wall
What is a retaining wall?
A wall that holds back earth or water
What is underpinning?
Method for repair & strengthening foundations. Could be used for:
- stabilising foundations undergoing settlement
- increase load capacity of existing foundations
What is superstructure?
- structural components of a builds constructed above the ground level (everything above damp-proof course)
What is the envelope of a building?
- the boundary between the interior & exterior of a building
What is a retained facade?
- where the facade of a building is preserved whilst the rest of the structure is remodelled, or a new structure built behind it
- often used when restoring listed buildings
What key information can you tell me about bricks & blocks in the UK?
Bricks
- standard size 215mm x 102.5mm x 65mm
- 60 bricks per m2
Blocks
- 10 blocks per m2
What is a curtain walling system?
- comprise lightweight aluminium frame onto which glazed or opaque infill panels can be fixed
What is a movement joints?
- designed to safely absorb the expansion & contraction of construction materials
- also allow for movement associated with ground settlement
What are the main components of concrete?
- cement
- aggregate
- water
What is the difference between dead & live loads?
- Dead loads: static forces that are relatively constant for an extended time. E.g. materials / non-structural elements such as kitchens, immovable furniture
- Live loads: the dynamic forces from occupancy & intended used such as weight of people, furniture, appliances, movable equipment
What is a glulam beam?
- stands for glue-laminated timber
- made with multiple layers of solid wood, bonded together with high-strength adhesive to form a single structural unit
What is reinforced concrete?
- concrete with reinforcements, such as steel bars, rods or mesh
- made to use the compressive strength of concrete & tensile strength of steel
What are the advantages & disadvantages of timber frames?
Advantages:
- Pre-fabricated, so construction on-site can be faster
- relatively lightweight
- seen as aesthetically pleasing for exposed frames
- sustainability benefits
Disadvantages
- skilled workmanship is not required to achieve a high-quality finish
- potential for wet rot, dry rot & woodworm
- fire protection may be required
What are the advantages & disadvantages of steel frames?
Advantages:
- faster to erect than concrete frames
- recyclable
- high strength to weight ratio
- beams can span over long distances (ideal for warehouses)
Disadvantages:
- lower load bearing capacity compared to concrete frames
- fire protection may be required
- price of steel can be volatile
- do not have the same acoustic & thermal properties of a concrete frame
What are the advantages & disadvantages of concrete frames?
Advantages:
- fire protection is inherent within the structure
- cladding & other finishes can be fixed directly to the frame
- provides good sound & heat insulation
- high compressive strength
Disadvantages:
- require formwork
- slower to construct on site
- requires a bulky structure
- concrete does not span as well as steel
- long curing time
In relation to concrete frames, what is formwork?
- the structure, usually temporary, used to contain poured concrete & mould it in to the required dimensions
- usually stripped away once the concrete has hardened & can support itself
What is the difference between a Cat A & Cat B fit out?
Cat A:
- typically provides a basic level of finish which may include raised floors, suspended ceilings & partitions, along with basic M&E services
- often a bare-bones finish that is considered a blank canvas for interior designers
Cat B:
- follows on from Cat A to provide a space that is ready to move into & operation
- may include floor finishes, furniture, branded material & decor
What is rainscreen cladding used for?
- it manages the flow of rainwater on a building
- not necessarily waterproof but serves as a screen & protection against rain for the rest of the building
What are the different types of site investigations?
Desktop survey:
- looks historically at maps & archive records to determine previous uses of the site
- carried out purely through research, rather than physical investigations
Site survey:
- walkover survey is where details & features of the site is taken
- highlights any immediately apparent geological, ecological, topographical or other issues which may present constraints to the project
Trial pits:
- excavation of an area of ground to study or sample the composition of the subsurface
- usually dug during the site investigation, soil survey or geological survey, & used to determine the geology & water table of the site
Borehole investigation:
- done alongside or as part of the trial pit
- determines any filled or contaminated ground, ground water, obstructions & bearing capacity of the soil
What is fire compartmentation within a building?
- a form of passive fire protection
- the idea is to subdivide a structure into fire compartments to limit the spread of fire & smoke in the building
What is intumescent paint?
- a passive fire protection system
- when exposed to extreme temperatures, it rapidly expands to protect the surface it is applied to
- this prevents, minimised or delays fire damage to the structure
What are automatic fire sprinklers & how are they activated?
- active fire protection system
- heat activated
- when the fire reaches a sprinkler head, a solder link will melt or a liquid filled glass bulb will shatter to activate the sprinkler, releasing water directly over the source of heat
What is the difference between passive & active fire protection?
Passive - containing the fire & preventing it from spreading further
Active - about detecting, stopping & escaping the fire
What are the Building Regulations?
- ensure that new buildings, conversions, renovations & extensions are going to be safe, healthy & high performing
- they cover specific topics such as fire protection, energy performance, structural integrity & acoustic performance
Who reviews the design & construction phase for compliance with Building Regulations?
- building control officer
- improved inspector
Can you name any materials banned from use in construction?
- asbestos
- high alumina cement
How does RIBA Plan of Work provide a defined process?
- renowned industry model for planning, designing & developing construction projects
- provides a consistent approach to delivering projects
- includes clear stages
What are the RIBA POW stages?
0 - Strategic Definition 1 - Preparation & Brief Concept Design 2 - Concept Design 3 - Developed Design 4 - Spatial coordination 5 - Construction 6 - Handover & Close-out 7 - In Use
How do Building Regulations impact design & construction?
- set out how and the standards to which a building should be constructed
- for example, Approved Document B sets out minimum requirements for fire escape routes
- this will impact on the positioning of rooms, doors and lengths of corridors
How does the Health & Safety at Work Act impact design & construction?
- It’s the overarching piece of legislation covering occupational health & safety in Great Britain
- it sets out general duties which employers have towards employees & members of the public and employees have to themselves & each other
- this will impact how a construction site is operated
You mention stud partitions in relation to inter-relating elements & components. How is this constructed then?
- a frame of metal or timber studs secured to the floor, ceiling & walls
- the frame is then covered with plasterboard
What is first and second fix?
- First fix: When the cables, wiring & circuits are installed. Done before any plastering work and in conjunction with any central heating or plumbing work
- Second fix: After plastering work, when fixtures are connected. For example, face plates on light switches & plug sockets, light fittings,
What is pre-fabrication?
- The construction of a buildings components off site, usually in a factory setting
- Then transported to & assembled on site
What is modular construction?
Where a building or module is constructed off site as a self-contained unit usually in a factory setting
Then transported to site
What are the advantages of modular construction & pre-fabrication?
- material efficiency - does not produce waste as they arrive on site in the finished state, better material planning in factories, less material loss from damage or theft
- cost efficiency - reduction in construction time, discounts through mass production of components, saves on labour hours and manpower cost
- reduced site disruption - reduces disruptions such as noise, pollution, and plant traffic
- time efficiency - due to all of the above
- safety - risks associated with on site construction such as hazardous waste, weather are reduced as they are constructed off site in a safe, controlled environment
What are the disadvantages of pre-fabrication & modular construction?
- Based on the concept of mass-production and standardisation so poses restrictions on designers designing unique buildings
- Restricts additions & alterations - difficult to make amendments
- High transportation costs
- risk of damage during transit
What do you know about pitched vs flat roofs?
Pitched roofs:
- creates more roof space than flat roofs
- has a longer life span than flat roofs
- are more effective at draining water than flat roofs
- are more expensive to construct than flat roofs
