Construction Tech - Level 1 Flashcards

Question

What are the disadvantages of concrete frame construction?

Answer 1

Needs to be cured on site, which can affect the strength. Cracks can appear due to shrinkages and live loads Labou itensive on site set up

Answer 2

Easy installation, accurately engineered to fit together onsite. Cost effective, minimal waste as manufactured off site. Does not degrade like timber. Durable

Answer 3

High maitenance costs. Requires fireproofing. Long lead-in times. High up-front costs.

Answer 4

Maximising value, through eliminating unwanted costs whilst improving functionality. Value engineering is not simply cost cutting, it can in fact lead to an increase in cost sometimes. To succeed in VE, increases in value must be achieved with a lower cost impact. Similarly, decreases in value must be met with a greater reduction in cost.

Answer 5

Achieving value for Money, through identifying what is most important and ensuring that function is achieved. Remaining budget if any can be spent elsewhere on less important functions.

Answer 6

Identifying and evaluating each cost, to ensure it is no greater than it needs to be to carry out its function.

Answer 7

Where a developer pays the council a contribution to offset the negative impacts caused by construction and development. Town and Country Planning Act 1990

Answer 8

A highway that is constructed by the developer to the Local Authorities standard, which may become adopted by the Local Authority and maintained at the public's expense. Highways Act 1980

Answer 9

• An agreement between a Local Authority and a Developer outlining the modifications required to an existing highway as part of a new Development. Highways Act 1980

Answer 10

European Design Codes.

Answer 11

Standards for the quality of goods and services within Britain.

Answer 12

The Highways act, governing the creation, maintenance and improvement of UK highways.

Answer 13

The Party Wall Act 1996.

Answer 14

A framework for preventing and resolving party and boundary wall disputes, when one owner of the party wall disagrees with works the other owner is undertaking.

Answer 15

An agreement (legal) which gives a Utility Company the right to use and access a specific area of property.

Answer 16

Community Infrastructure Levy.

Answer 17

A form of easement to allow an existing building to maintain the same level of light, despite of new developments. The '50:50 rule' however, may be deemed adequate. This involves determining what percentage of a room receives adequate light on a working plane 850 mm above the floor. An injury may be considered to have occurred where the percentage is reduced to less than 50%. Where more than 50% of the room still receives adequate light however, an injury may not be considered to have occurred, irrespective of the amount of light that has been lost.

Answer 18

Where say a crane or scaffolding has to pass over another person’s land, this will require a license.

Answer 19

1. Roof Covering (Waterproof Layer). 2. Insulation. 3. Vapour Control Membrane. 4. Decking 5. Roof Joists. 6. Ceiling

Answer 20

1. Roof Cover (Waterproof layer) 2. Decking. 3. Roof joists (infilled with insulation). 4. Ceiling.

Answer 21

• Single Ply membrane. • Mastic Asphalt. • Built-up felt.

Answer 22

• A warm roof will make the entire building structure warm, in an attempt to avoid any cold bridging. • A cold roof is where the insulation is placed beneath the roof space, leaving the roof space cold. This will either need to be ventilated or have a breather membrane.

Answer 23

- Waterproof membrane easily accessible for repair and maintenance - Insulation does not need to take load so wider choice of material available - Do not need to increase height to upgrade insulation, therefore overcoming potential planning restrictions

Answer 24

- Relies on ventilation removing moisture that may enter roof space, which is often difficult to provide in sheltered areas where there is less air movement - Difficult to maintain integrity of VCL due to its position (e.g. punctured by light fittings or other services) - Moisture from outside can enter roof space through ventilation gaps and can condensate in cold weather - Likelihood of thermal movement occurring in the deck is increased due to direct exposure to heat from the sun (not protected by insulation as per warm roofs)

Answer 25

Warm 'Sandwich' Roof: - Insulation is placed above the deck but below the waterproof covering, i.e. forming a 'sandwich' between the deck and the waterproofing Warm 'Inverted' Roof: - Insulation is placed above both the deck and the waterproof membrane, i.e. the waterproof layer is inverted from its 'normal' position

Answer 26

- Roof structure is protected from extremes of heat and cold (potential damage caused by thermal movement is reduced) - Less likelihood of condensation occurring in the warm roof space - Waterproof membrane easily accessible for repair and maintenance

Answer 27

- Any water from leaks or water vapour passing through VCL may get trapped in insulation - Possible that thermal movement within insulation layer could damage waterproof covering (although can be overcome by careful selection of insulation or by placing an isolating layer between insulation and membrane) - Waterproof membrane is exposed to a greater range of temperatures (receives no heat from the building in cold weather and cannot dissipate solar heat in warm weather due to the insulation below) - Insulation must be able to resist impact of foot traffic

Answer 28

Waterproofing material originally consisting of lake asphalt mixed with limestone aggregate naturally impregnated with bitumen Modern high-performance asphalts are polymer-modified products which perform better in thermal shock and low temperature bending tests

Answer 29

Can degrade far quicker on traditional warm-decked 'sandwich' roofs, as solar gain is focused into the waterproofing Therefore, performance is better on cold decked roofs or inverted warm roofs

Answer 30

Double-lapped to prevent water ingressing into the roof space through gaps between each tile (i.e. there must always be two layers of slate at any one point and three at the laps) Can be either centre-nailed or head-nailed (the latter ensures the nails are protected by two layers of slate, but are more at risk of lifting in high winds, especially on low-pitched roofs) Non-ferrous nails such as copper or aluminium are recommended (galvanised steel can lose its coating, which is quite soft, when nailed and is therefore free to rust) Minimum pitch: 30 degrees

Answer 31

Double-lapped like slate Have nibs enabling them to hang from the battens, meaning nailing every tile is unnecessary (usually every 4th or 5th course and all around the roof perimeter), unless on steep pitches or very exposed situations where every tile should be nailed NB: avoid using galvanised steel or ferrous nails Minimum pitch: 35-40 degrees

Answer 32

A cold bridge is an area in a building where a gap occurs in the insulation (for example: the roof/wall junction and the wall/floor junction). As these areas will be colder than the main areas there is a greater risk of condensation forming. With condensation comes the added problem of mould.

Answer 33

Designing out areas where cold bridging can occur, i.e. junctions between walls, roofs and floors will help the sustainable performance of a building.

Answer 34

Operation and Maintenance Manual.

Answer 35

• It is a manual prepared by the Contractor, containing information on the Operation, Maintenance, Decommissioning and demolition of a building. • It should be updated by the owner whenever changes to the buildings fabric are made.

Answer 36

• A description of the Main design principles. • Details of building construction. • As-built drawings and specification. • Instructions for the operation and maintenance of the building. • Commissioning and testing results. • Guarantees, Warrantees and Certificates. • Particular requirements for Demolitions, Decommissioning and Disposal.

Answer 37

• A file prepared as part of the Construction (Design and Management) Regulations, by the Principal Designer. • It should identify the risks that could not be eliminated through design, whilst also including information provided by the Principal Contractor. • The file should be regularly updated when changes to the building are made.

Answer 38

• Description of the works carried out. • Any hazards that have not be eliminated through design and how they have been addressed. • Key Structural Principles. • Location of hazardous materials • Information about the removal of installed plant and equipment. • H&S information about cleaning and maintaining the structure. • As built information for services etc.

Answer 39

• Dust. • Noise. • Vibrations. • Plant Instability due to Ground Conditions. • Contaminating existing ground.

Answer 40

• Driven Piles, also known as displacement piles. • Bored Piles, also known as replacement piles. • Secant Piles, used to create retaining walls.

Answer 41

• A form on contiguous piling, which can be used to create retaining walls. • Initial piles are bored with gaps, and cast with no reinforcement and a weaker concrete mix. • The stronger, insitu piles are bored in the gaps and partially through the existing piles, which care poured in a stronger concrete mix with reinforcement cages.

Answer 42

• Concrete piles. They can come in pre-cast for driven piles, or be poured in-situ. • Steel piles. They are pre-made, and can be used when driving piles. • Timber piles. They are pre-made, also used when driving piles.

Answer 43

• Rafters (Trusses) sit on a wall plate and meet at the top off the roof at the Ridge Board. • If creating a warm roof, insulation will site above this with a waterproof membrane, roof felt, batons then tiles.

Answer 44

• Strip Foundations. • Pad Foundations. • Raft Foundations. • Piled.

Answer 45

1. Excavate the trench. 2. Level and compact the bottom. 3. Put down heave protection if required, e.g. ground with lots of clay. 4. Pour concrete into the trench, mass fill. 5. Tamp and vibrate to remove air bubbles and give a flat finish. 6. Get signed off by the building inspector.

Answer 46

• Battered Earthwork Support. • Sheet Piled. • Secant Piled.

Answer 47

Steel frames – usually have less columns and a wider span between the columns Concrete frames – usually have more columns , lower floor to ceiling heights and a shorter span between the columns

Answer 48

Amosite - Brown Crocidolite - Blue Chrysotile - White Used mainly as an insulator and building material up until year 2000

Answer 49

Decontamination enclosure of work under negative pressure. Shadow vacuuming

Answer 50

BS EN 1992 - usually between 25-50mm but depends on a number of factors including diameter of the steel, concrete strength class, environmental conditions, use of additional protection and an allowance for deviation on site

Answer 51

- Intumescent coatings - paint like material that expands at high temperatures to form a protective layer around the steel - Sprayed coatings - cementitious based material that forms a protective layer around the steel - Encasement - fire-rated boards can be used to encase the steel, offering protection against fire as a dry trade alternative - Flexible blanket systems - fire protection material that can easily encase steel of a complex shape where application must be completed as a dry trade - Concrete encasement - used commonly until the late 1970s when boards and coatings were introduced

Answer 52

- Means of assessing the consistency of fresh concrete and that the correct amount of water has been added to the mix - Three equal layers of the mix are poured into a steel slump cone (rodding each layer to ensure compaction), the cone is then removed and if the concrete collapses or a layer shears off, it would mean too much water is in the mix

Answer 53

- Foul - used water from any building or process, including water from toilets, showers, washing machines, kitchen sinks etc. - Surface - water that has drained directly from the ground, pavement or roof - Combined - a mix of both foul and surface water and carries both in a single pipe

Answer 54

A high-density polyethylene (HDPE) geotextile membrane can be used to line excavations in order to prevent roots attacking vulnerable underground pipework joints

Answer 55

Common brick - basic clay brick, no attempt at colour/texture control or special surface treatment Facing brick - more attractive, sides more accurately finished and smoothed, colours more uniform Engineering brick - used where strength, low water porosity or acid (flue gas) resistance is needed

Answer 56

Outer leaf (i.e. facing bricks) Cavity Insulation board Inner leaf (i.e. aerated blocks) Wall ties DPC (on each leaf, 150mm minimum from ground level) Backfill (weak concrete mix below ground)

Answer 57

Cast or wrought iron first used until approximately the 1930s Galvanised steel (coated in zinc to protect the steel electrochemically, slowing the corrosion process) used thereafter, although minimum thickness of zinc cover was reduced in 1968 (but later increased again in 1981) Part A now requires stainless steel (ferrous alloy containing at least 10% chromium, forming a 'self-healing' impermeable layer of chromium oxide on the surface of the steel thus preventing the formation of rust) to be used Plastic ties are also now commonly used

Answer 58

Part A requires a 900mm horizontal spacing and 450mm vertical spacing, or no less than 2.5 ties/m² Extra ties are required around openings (300mm vertically, within 225mm from the vertical edges)

Answer 59

Mullion - a vertical bar/member dividing a window Transom - a horizontal bar/member dividing a window

Answer 60

Metal connector plate (or 'wall starter system') bolted to the existing wall and metal wall ties tie in the new wall at appropriate intervals - advantageous as it is quick, easy and best used if the old brickwork is of a different size/colour to the new Tooth-in new brick work with the existing brickwork - consider colour matching (may need to try and conceal the join behind a rainwater pipe or set the new wall back from the face of the existing to provide a shadow gap)

Answer 61

A weather-proof, non-loadbearing enclosure of windows or metal panels in a light metal framework which is fixed back to the structure of a building, usually at intermediate floor levels.

Answer 62

Individual pieces of lead equal in length to the gauge (centre to centre of the battens), plus the lap, plus 25mm (to allow for turning down over the tile to prevent it from slipping) Installed beneath a separate cover flashing to form a good waterproof junction and prevent the flashings lifting in high wind

Construction Tech - Level 1 Flashcards

(87 cards)