Construction Tech Flashcards
1
Q
What is Radon?
A
◼ Colourless, odourless, radioactive gas
◼ Poses a risk to health in high concentrations e.g. builds up in enclosed spaces such
◼ as basements
◼ Health Protection Agency — published a map of radon affected areas in the UK
◼ Passive monitors and detectors should be installed in homes in affected areas and
◼ tested for a period of 3 months
◼ Remedies include;
◼ Prevent radon entering a building by altering the pressure balance between inside
and outside
◼ Sump pump below floor and connected to a fan Improve ventilation in suspended
floors
◼ Install a fan in the roof space
◼ Install a membrane barrier — seal all ducts, joints, cracks in building
◼ Governed by Building Regulations Approved Document C
2
Q
What is the external envelope?
A
The materials and components that form the external shell or enclosure of a building
May be load or non-load bearing
3
Q
What are retaining walls?
A
They act as an earth retaining structure for the whole or part of their heights
Need to consider water pressure and pressure of the retained earth in their design
4
Q
What is single lap tiling?
A
Typically, tiles utilise a ‘tongue and groove’ detail to maintain weather
tightness. Lighter construction but requires larger roofing battens and
mechanically fixed every 2nd course.
Can be used on shallow pitches.
5
Q
What are the technical disadvantages of concrete frames?
A
More time consuming. Slower to construct
Edges may not be as square and surfaces not as flat as steel
The need for steel reinforcement leads to some of the cost issues associated with
steel
Heavier so requires larger foundations
6
Q
What colour pipes are building services?
A
− Yellow Pipes (Gas)
− Blue Pipes (Water)
− Brown / Grey Pipes (Drainage)
7
Q
What is Type A Tanking?
A
- Continuous waterproof membrane applied to slab and walls (internally or
externally)
External best as it protects against sulphate attack
External cannot be applied retrospectively
Mastic asphalt traditionally used but polymers now available
8
Q
How many bricks are in a m2?
A
There are about 60 bricks per m2.
9
Q
What are international standards?
A
Prepared by the International Organisation for Standardisation – prefixed ISO
Compatible with and complement BS’s
10
Q
What is Legionnaires disease?
A
• Legionella is an aquatic organism (bacteria)
• Most prevalent at 40-65% relative humidity - the perfect comfort level for people
• Can be vaporised from showers and humidifiers and be inhaled causing
Legionella Pneumonia
• Legionella Pneumonia can be fatal!
11
Q
Where would you go to find out if a material was banned from use in
construction?
A
British Standard Online – British Standards Specification
12
Q
How is water provided for a sprinkler system?
A
From the mains
A pumped Supply
A pressurised supply
13
Q
What is the size of a brick?
A
Standard bricks are 215mm x 102.5mm x 65mm
14
Q
Tell me more about soil investigations?
A
Purpose is to determine the suitability of the site for the proposed works and
determine adequate and economic foundation design
Should determine the potential difficulties
The method chosen will depend on type of building – function, size etc
15
Q
What are the main site considerations?
A
Access considerations – approach roads etc Storage considerations Accommodation Temporary services Plant Fencing / hoarding Safety and health
16
Q
What is bottom up construction?
A
“Bottom up” forms the basement and then works upwards in a traditional manner.
Simpler but a longer programme.
17
Q
What are the main components of a hipped end pitched timber roof
structure?
A
Principle Rafters – Provides support to roof covering. Span from eaves to ridge
Jack Rafters – Shorter rafters that run from hip to eaves or ridge to valley
Ridge board – Spine of roof carcass than runs along the ridge
Hip rafters – where two roof surfaces meet to form external angle
Valley rafter – where two roof surfaces meet to form internal angle
Bargeboards / fascia – to cover feet of rafters
Purlins – Intermediate horizontal members to support rafters
Battens – small pieces of wood to which the roof covering is affixed
Covering – either laid or fixed on to a roof to protect from the elements. Types used
are:
Slates – interlocking or plain
Pan tiles – burnt interlocking clay tile into an ‘S’ shape (Mediterranean style).
Zinc
Copper
Thatch
Wall plates – to receive the feet of rafters at top of external wall
18
Q
What is a basement?
A
A storey below the ground storey
19
Q
What are the different types of brick bond?
A
Stretcher – most common, walls just a half brick wide
English – alternating courses of headers and stretchers
20
Q
What are panellised systems?
A
• Like unitised systems, panellised curtain walling is constructed in the
factory to improve quality control and speed of erection. However, the
systems comprise large prefabricated panels of bay width and storey
height, which are connected back to the primary structural columns or to
the floor slabs. Panels may be of precast concrete or comprise a structural
steel framework and are often clad with a variety of stone, metal and
masonry cladding materials.
• The advantage of these systems is improved adherence to specification as a
consequence of factory prefabrication, allowing improved control of quality
and rapid installation with the minimum number of site sealed joints.
Panellised systems are less common and more expensive than unitised
construction.
21
Q
What is slip forming?
A
A method for constructing a repetitive structure such as a core, lift shaft or stairwell.
The formwork is constantly moving upwards, approx. 1” every 10mins.
The concrete that becomes exposed must be cured enough to support.
22
Q
What is the difference between rolled and tiled carpet tiles and why do
we use each type?
A
Rolled carpets generally better quality and more expensive. Used in dwellings.
Carpet tiles – harder wearing, lower quality cheaper and individual tiles can be
replaced therefore easier to maintain. Used in offices, hospitals etc. Also where
raised flooring systems are used carpet tiles allow for easier access to services that
run in the void below.
23
Q
What are piles?
A
A series of columns constructed or inserted into the ground to transmit the load of a
structure to a lower level of subsoil
Used where no suitable foundations conditions near ground level or high water table
24
Q
Name some types of shallow foundations?
A
- Pad
- Traditional Strip / ground beams
- Solid Slab Raft
- Deep Strip / Trench fill
25
Detail an inverted Roof?
• A roof in which the insulation is placed on top of the waterproof membrane.
• No vapour control is needed.
• Roof void and or deck are maintained at similar temperature to the room.
• The insulation protects the membrane from damage but must
be anchored down.
26
What would you consider when selecting the type of pile to use?
Use - Point Load from frame, Retaining Wall, Basement, Sheet pile to strengthen
embankment
Cost
Depth of piles
Contractors experience of difficult sites
Ability to complete works in a phased programme
Cost of extensive testing
Type of soil (displacement / replacement piles)
27
What is settlement?
◼ All new structures settle following construction
◼ Extensions may settle differently to older parts which have already settled. This
needs to be accounted for in the design e.g. suitable foundations, expansion joints
28
What are the technical advantages of concrete frames?
Examining the impact of the steel price rises has found that the whole project costs
for concrete framed buildings are marginally less than for steel framed buildings.
Fire protection as part of structure
Slower form of construction at this early stage will reduce the cash flow early on
Maintenance of an insitu concrete frame is low
Cladding can be fixed to it and replaced easily.
It also provides good sound and heat insulation.
Insitu allows for alteration at late stage of construction
Can deal with complex geometry better than steelwork
29
What is subsidence and wjat are the signs?
• A symptom of when; the loads applied exceed the bearing capacity of the ground,
or;
• Loss of support beneath the foundations (insufficient foundations, leaking drainage
causing erosion, trees taking up moisture in clay or dry periods of no rainfall, old
mines)
• Distortion / movement of the roof covering / dip in the roof ridge Dropped heads to
door and window openings, openings not square (binding)
• Cracking will pass through DPC
• Shear cracking is vertical movement,
• Tapered if rotational
• Tapered cracks are wider at the top than the bottom
30
Sketch an eaves detail of a typical warm pitched roof and name the elements.
...
31
What is inert & active waste?
Inert - aggregates /soil / stone / brick / concrete / plaster / glass.
Active - Timber / paint / demolition waste. "
32
What is a Remediation Notice (served by the LA)?
◼ Local Authority will first issue a notice for the owner / occupier to rectify
◼ After 3 months a Remediation Notice can be served
◼ Sets out the scheme proposed, any exclusions from liability and apportionment of
costs
◼ Notice can be appealed within 21 days if there is an error in the Notice,
timeframes are not adhered to or incorrect person has been contacted
- Class A person — known polluter
- Class B person — polluter unknown, so current landowner or occupier
33
What is the difference between bored/pre-cast piles? What are the
problems to the PQS regarding cost control with piling? Whose risk
is the piling?
Bored piles are defined when the process for removing the spoil to form the hole for
the pile is carried out by a boring technique. They are used primarily in cohesive
subsoils for the formation of friction piles and when forming pile foundations close to
existing buildings where the allowable amount of noise and/or vibration is limited.
Pre-cast Concrete piles are generally used where soft soil deposits overlie firmer
strata. These piles are usually driven using a drop or single action hammer.
34
What is scabbling?
Scabbling utilizes piston driven carbide tipped heads which impact the surface at a
rapid rate pulverizing concrete or brittle coatings. Scabbling can be very effective in
the removal of slightly bonded coatings or where the coatings are impossible to be
removed by the shot blasting process. It can also remove level inconsistencies in
concrete floors
35
When would you need to use piles?
1) Low bearing capacity of subsoils
2) Heavy point loads of structure exceed bearing capacity of soil
3) Presence of highly compressible soils near surface such as peat
4) Subsoils such as clay which are prone to movement
5) High water table"
36
Detail a cold roof?
• Insulation located at ceiling level
• Void or roof slab is insulated from heat loss from below and is therefore at a
colder temperature than the room during cold weather.
• Risk of condensation forming within the roof void or on the underside of
the slab, so good cross-ventilation is essential.
• Vapour control layers at ceiling level are essential, but not 100% effective.
37
What are hoists?
Design for the vertical transportation of materials or people
38
What fire safety provisions would you expect to find in an office
block?
Maximum occupancy listing (Making sure that an area isn't so full of people that they
can't all get out quickly in an emergency).
Fire exits and proper signage of them (e.g., Exit signs pointing to them that can
function in a power failure)
Placing fire extinguishers and fire alarms in easily accessible places.
Banning of over-flammable materials for building or use.
Frequently inspecting public buildings for violations and closing it until the violation is
corrected or condemn it in extreme cases.
Installing fire alarm control panels for quick detection and warning of fire
39
What is a strip foundation?
Suitable for most subsoils and a light structural design, usually reinforced
40
Detail reinforcement requirements for concrete floors?
• Steel reinforcement can be in-situ or pre-cast
• Typically, pre-stressed to provide tensile strength
• Minimum of 20 mm — 70 mm concrete cover is required to prevent corrosion
and provide fire protection.
• Comply with BS 8110 — Structural Use of Concrete
41
Name some of the main materials that have been banned from use in
construction?
High alumina cement in structural elements
Asbestos
Urea formaldehyde.
ACM cladding
42
Draw a typical trussed roof structure.
...
43
What is Type B Tanking?
Waterproof construction - Monolithic Concrete Walls and Floors
Dense high-quality reinforced concrete
Relies on good materials and workmanship (attention to detail)
Not always water / vapour proof
Not suitable for living / archiving areas
Risk of sulphate attack
44
What are British Standards?
Publications issued by the British Standards Institution – prefixed BS
They give recommended min standards for materials, components, design and
construction practices
45
What are the different types of piles?
Sheet piles – a deep trench is excavated and concrete is poured in situ. The piles
can be used to form basement walls or act as retaining walls.
Secant piles – interlocking piles (male and female, often different diameters and
hardness) are bored to provide a combination of foundations and basement walls.
They go someway in providing a waterproof structure. Secant piles are often seen
when a top down construction method is used.
Bored Piles – an auger is used to excavate the soil and then concrete is poured in
once complete. A variation to this is CFA (Continuous Flight Augered) where the
piles are bored, Bentonite slurry is pumped in to stop the core collapsing and then
concrete (which is denser than Bentonite) is poured in. Bentonite is environmentally
harmful and is therefore not often used in the 21st century.
Pre-cast piles – pre-cast piles are brought to site and hammered into the ground. Not
often favoured due to the high noise levels associated with installation and the lack
of flexibility in terms of depth required.
46
Who is responsible for compliance with the Building Regulations?
The person physically carrying out the works (ie. builder)
47
What are the typical components of site investigations?
- Objective is to systematically collect and record data to help in design / construction
- Should include anything on adjacent sites that may impact and:
- Boundary hedges / fencing
- Existing trees
- Size, depth and location of services – gas, telephone, electricity, water, drains
- Existing buildings
- Ground water conditions
- Soil investigations – trial pits etc
48
What are continuous bored piles?
• Piles are drilled
• Reinforced and concrete poured close together to form a perimeter
wall before excavation.
• Not water tight so only used in dry conditions. Drained cavity
systems also required
49
What is double lap tiling?
Traditional method where a minimum of two layers of tile are
present in any one location
Each tile has nibs and nail holes to be affixed to roofing battens
Typically, tiles are only nailed (mechanically fixed) every 4th
course, depending on wind conditions
Used with a plastic underlay (sarking / roofing felt underlay). Creates a
barrier to snow, wind, driving rain etc. Barrier should be breathable to
allow moisture / water vapour to escape.
50
What is Rainscreen cladding?
Rainscreens are not curtain walls as such, as they provide a screening
function rather than an enclosure in its own right. A rainscreen is used to
shield a wall, whether this be of masonry, metal studwork or in some cases
glass. Usually a rainscreen is designed to permit some controlled leakage
with the main functions of resistance to air and water being provided by
the shielded wall behind
51
The basement construction for your project is in between two
adjoining properties, were there any Party Walls issues? What is a
Party Wall award?
A Party Wall Award - an agreement to carry out works where there is a party wall
issue. Will involve a record of the current state of the wall, methods for carrying out
the works, hours of working, access, protection required. Provisions for inspection &
making good damage. Legally binding document.
52
What are the different types of Concrete finishes?
Top Surfaces:-
Tamp - basic - not measurable - makes top surface flat
Wood Float - provides smoother surface - works aggregate
Steel trowel - better quality finish.
Power Float - good quality finish for placing of vinyl/carpet.
Formed Surfaces:- Aggregate Exposure, Bush Hammering."
53
What is a foundation?
Function is to safely sustain and transmit to the ground on which it rests the
combined dead, imposed and wind loads of the structure
54
What is superstructure?
All internal and external structure above the substructure
Made up of primary (ext walls, stairs, roof, structural walls) and secondary
(suspended ceilings / raised floors, balustrades, doors) elements and finishes (tiles,
paint, stair nosings)
55
What other elements will be affected by the type of cladding systems
used?
Frame
Roof
M&E.
56
What are the technical disadvantages of steel frames?
Needs fire protection
Parts may need replacing
Price of steel is variable
Need experienced builders – additional cost
Even though steel components will not burn they will actually fail (collapse) before a
wood component in a fire.
57
What is contaminated land?
◼ Land may be contaminated with asbestos, oil, diesel, radon, etc.
◼ Affects land value and rental income
◼ Can be hazardous / damaging to people and buildings
◼ Covered by the Environmental Protection Act 1990
- Phase 1: Audit (desktop study)
- Phase 2: Survey (soil samples)
58
How is composite metal cladding fixed to a steel frame?
Bolted
Riveted
Welded.
59
What is an air brick?
A perforated brick to allow for ventilation into a room or an underfloor space. NOT a
weep hole.
60
What is the purpose of a threshold strip?
A lightly rounded metal strip over the joint between the floor finishes or coverings that
meet under the door leaf.
Prevents fraying, looks better and interrupts combustible flooring under fire doors
61
Where could you go to get Building Control approval on a project?
Your local authority building control services OR approved inspectors
Approved Inspectors are companies or individuals authorised under the Building Act
1984 to carry out building control work in England and Wales.
62
What happens if the building regulations are contravened?
Magistrates Court - Fine of up to £5k + £50 for each day it continues & must invoke
procedures within 6 months. Local Authority - May issue enforcement notice
requiring compliance or undertake works & recover costs
63
What is compartmentation?
− Prevent spread of fire
− Provides safe means of escape
− Structural elements should be protected to prevent collapse
− Approved Document B stipulates minimum requirements (30 or 60
mins) based on risk, use and location
64
What is a borehole?
A borehole can be used for soil investigation or for geothermal heating solutions.
Boreholes are the most suitable method of soil investigation when foundations are
over 3m deep
Geothermal boreholes are permanent boreholes that use the Earth’s natural heat to
raise the temperature of circulated water. This is a closed system and can be used to
heat the building above. It’s seen as a sustainable technology.
65
What is 'sick building syndrome'?
Contribution of factors within a building which may cause people to feel dizzy,
sick, flu, stress, dry eyes etc. including;
− Bacteria in air conditioning / ventilation
− Artificial lighting
− Heating provisions / humidity
− Noise levels
• To minimise the potential of 'sick building syndrome' use natural ventilation,
correct lighting levels and place plant / machinery such as photocopiers in
separate rooms
66
What is stick system cladding?
• In the stick system, the curtain wall frame (mullions) and glass or opaque
panels are installed and connected together piece by piece.
• Stick curtain walling systems are versatile and allow for the integration of
other systems, such as sliding doors and windows. They tend to be less
specialised and can be built by all types of fabricators as they are not
dependent on having a large factory.
• However, stick systems do require multiple steps to erect and seal the wall,
which means more time is spent on site – an approximate rule of thumb
would be that 70% of the work is carried out on site, with 30% in the
factory. This incurs further costs, such as labourers’ time.
67
What are the elements of a flat roof?
Joists – fixed to wall plates to act as main support
Furrings – fixed to the top of joists to give required incline
Particle board – fixed to top of furrings to give flat surface
Felt – 3 layers bonded with bitumen to give waterproof covering
Stone chipping – To give protection to felt and to reflect sunlight
68
How is a foundation type determined?
The type of foundation is determined by;
Ground conditions and load bearing strata
Depths
Composition (stone, rock, sand, clay, peat)
Water table
Loads to be imposed (point loads, uniform loads, etc.)
69
What is the aim of the Landfill Tax?
To reduce waste & encourage recycling & waste management
70
Advantages and disadvantages of timber frame?
```
• Advantages:
- Sustainable
- Cheap and Quick
• Disadvantages:
Excess moisture / damp can lead to structural degradation
Risk of insect or fungal attack
Risk of fire spread —Special fire codes
Differential movement between brick skin and timber frame
```
• Most common in residential construction
• Less weight than traditional masonry methods
• Alternative to traditional standard loadbearing masonry due to speed of construction
• Lighter construction means smaller foundations
• BRE recommends a maximum of 6 storeys for timber frame
• 2 Types:
Balloon Frames
+ Walls constructed as complete entities (all stores on 1 panel)
+ Floors are suspended from panels.
+ Restricts number of storeys.
Platform Lift
+ Walls constructed as a storey height element
+ Prevalent in the UK
+ Better suited for pre-fabrications
71
What are the different ways that the piles transfer their load to the
surrounding ground?
End bearing piles
Friction piles
Settlement reducing piles
Tension piles - tall chimneys, transmission towers and jetties
Laterally loaded piles - bridge piers, trestles to overhead cranes, tall chimneys and
retaining walls
72
Detail a Warm Roof?
• Insulation placed on top of the roof deck but beneath the waterproof
membrane.
• Vapour control usually placed under the insulation.
• Reduced risk of condensation as the ceiling or roof void is at a similar temperature
to the roof.
73
What types of fire detection are there?
− Manual (break glass call point)
| − Automatic (heat / smoke detectors)
74
What is substructure?
All structure below the superstructure i.e. all structure below ground level including
the ground floor bed
75
Draw a Queen Post Roof
...
76
What is an MF ceiling?
Mineral Fibre plasterboard suspended ceiling.
77
How do Sprinklers work?
◼ Triggered manually or automatic
◼ Sprinkler heads typically have a temperature sensitive element
◼ Pipe work is usually steel to offer increased fire protection
◼ Spacing
− Each head covers approximately 12m2
− Heads are spaced every 4 LM and 2 LM from walls
◼ 2 types of system
− Wet Systems
+ Permanently charged (water at head, instant)
+ Common when there is no risk of freezing
− Dry (Air Charged) Systems
+ Charged with air under pressure
+ When air pressure released water flows
+ Common when there is a risk of freezing
78
What are Dry and Wet risers?
◼ Similar to sprinkler systems
◼ Allows fire services to deliver considerable quantities of water
◼ Typically, found in:
− Buildings over 18m
− Low rise buildings (large footprints)
− Wet risers found in buildings over 60 meters high
79
What types of ground investigation are there?
Trial Pits, Boreholes, Ground Sampling, Site tests, Observations, Instrumental
Observations - settlement gauge, Laboratory Tests - Soil strength.
80
What are the Building Regulations?
Statutory instruments that sets out the minimum performance standards for the
design and construction of buildings
Supported by the Approved Documents A to P and other codes of practice
81
Can you identify some sustainable heating options?
Biomass CHP system - Uses waste products & wood chippings / pellets to generate
heat & electricity. Initially expensive to set up but cheap to run. Ground Source Heat
Pump - Generates heat by pumping water into the ground and abstracting heat from
the warm water.
82
What are the different parts of a steel beam?
A simple I Beam is made up:
Flange (Top and Bottom of the vertical steel)
Web, which is the vertical steel part of the I
Root, which is where the Flange and the Web join.
83
What is intumescent paint? How do you apply intumescent paint?
Fire Resistant paint, sprayed on in the factory. Touched up by hand on site.
84
What are unitised systems?
• Unitised systems comprise narrow-width, storey-height units of aluminium
framework containing glazed and/or opaque insulated panels. The entire
system is pre-assembled under factory-controlled conditions.
• The unitised panels are usually craned into position, with pre-positioned
brackets attached to the floor slab or the structural frame. Modern
installation techniques increase the speed of erection and often minimise
the requirement for scaffolding.
• Unitised systems do have higher direct costs.
85
Who ensures the building regulations are complied with?
Building Control Services - Local Authority / Approved Inspectors (Private companies
set up to specifically regulate building control)
86
What are the 3 main methods of waterproofing a basement?
Dense monolithic – this is where the basement is designed and built to form a
watertight space using high quality reinforced concrete, needs good workmanship
and strict control. Success will depend on water / cement ratio and degree of
compaction. Joints need to be carefully designed
Tanking – e.g. asphalt, polythene sheeting, bitumen, epoxy resins. These can be
applied internally or externally to provide a continuous membrane to the base slabs
and walls. Externally is better as it protects the structure as well.
Drained Cavity – can be used for new or refurbishment work. It accepts a small
amount of water seepage will occur, and collects and drains this away. Builds an
inner non-load bearing wall to form a cavity. The floor is laid to falls, moisture drains
to a sump and is discharged direct or pumped
N.B. Basements are rated as to their final use e.g. habitable, plant, storage and the
waterproofing solution is often influenced by this.
87
What are the main components of concrete?
Cement, aggregate (natural rock, crushed stone, gravel) and water
88
What are Secant Piles?
* Overlap
* Method similar to contiguous bored piles but piles interlock
* Water tight.
89
What is top down construction?
| “
“Top down” is used to speed up the construction process of a building with basement
levels. The ground floor slab is cast with an access hatch. The ground below is
excavated and another slab is formed. If there is another level, the process is
repeated. Piles are usually used as foundations and also act as retaining walls. It
allows the building above to be constructed at the same time as the basement.
90
What is powder coating?
A though durable factory applied organic coating on metals, such as aluminium or
galvanized steel, available in many colours.
E.g. polyester, polyurethane, acrylic, and epoxy which are sprayed on, followed by
heat curing to give a film thickness of 50 to 100micorns.
Any holes should be made and any cutting done before the coating is applied.
91
Name some types of Deep Foundations?
• Pile foundations are recommended when depths of 3 m or more are required
• Pile foundations are a series of columns constructed or inserted
into the ground to transmit the loads of a structure to a lower level
of the subsoil'
• Bentonite is used with replacement piles to stabilise excavations and
support sides of the bore hole prior to concrete fill
• Lack of suitable ground conditions may be caused by
Natural load bearing capacity of sub-soil
High water table - giving rise to permanent dewatering cost
Presence of layers of highly compressible subsoil's such as peat and
recently placed pilling materials (made up ground
92
What is a retained façade?
The facade of the building is retained whilst everything behind the front wall is
demolished.
Allowance needs to be made for a temporary support structure and also cleaning/
restoration works to the retained façade. Often listed.
93
What are the technical advantages of steel frames?
Quick to assemble,
100% recyclable - inorganic - will not warp, split, crack or creep –
Highest strength to weight ratio of any building material –
Not vulnerable to termites or any type of fungi or organism
Dimensionally stable - does not expand or contract with moisture or temperature
changes.
Consistent material quality - produced in strict accordance with national standards,
no regional variations
Light steel components are always straight
Steel is non-combustible so it will not contribute to the spread of a fire.
Lighter therefore poor soil conditions will need steel over concrete
94
What is Part L?
Conservation of fuel and power. Involves minimising heat loss through the building
fabric, heating & hot water systems, & power used in artificial lighting. (Applies to
dwellings or buildings with floor area exceeding 30m2 / 100m2)
U Value - Measure of Heat Loss through an element e.g. Glazing, The lower the U
Value the more efficient the element.
95
What type of building work is covered by the regulations?
1) Erection or extension of a building
2) Installation or extension of a service controlled by regs
3) Alteration project which will temporarily or permanently affect the building (in terms
of structure, fire & access)
4) Insertion of insulation into cavity wall
5) Underpinning building foundations"
96
How do you construct a glass partition?
The glass is ‘glazed’ or fixed into a frame, be it either a wooden or a steel frame.
The glass is placed in a rebate and secured with putty or beading.
This frame is then mounted between the walls / columns required and usually
secured with a putty.
97
Different metal frame structures?
• Light weight Skeleton frame (traditional)
- Series of rectangular frames at right angles
- Roof and floors span between the beams
• Steel frame
Utilised for both multi storey structures and
individual buildings
Range of options for industrial use but 'portal frame' most prevalent in the UK
Specialist and expensive
Quick construction
Steelwork connections either shop connections or site connections.
Requires fire protection.
Lighter then concrete so smaller foundations required.
Longer lead-in time for steel
• Portal Frame
Over all span 20 m — 60 m. Each portal unit is 4.5 m - 7.5 m. Unit is braced
by purlins and wind / cross bracing
Comprises of columns on fixed or hinged bases
supporting rafters to form a rigid frame
Hinged bases preferred as smaller foundation required and cheaper construction
Fixed bases used for areas of high horizontal forces
Haunches provide additional rigidity for frame stability
Typical eaves height range between 4 m — 12 m
98
What is the frog and which side does it go on?
The frog is an indentation in one of the bed faces of a brick, usually the top.
Bricks with two frogs are known as ‘double-frogged’, though these are less common.
Unless specifically stated, bricks should be laid frog (or larger frog) facing up, and
with mortar filling the frog.
This gives a stronger wall and superior sound insulation.
99
What are the main types of excavation?
Open – use battered excavation sides cut back to a safe angle, eliminates the need
for temporary support work, can easily construct basement walls and fall BUT extra
excavation costs and need a lot of free site space
Perimeter Trench Excavation – trench dug wide enough to form basement walls, this
is supported as required – basement walls are constructed and then the inside of the
basement is excavated.
Complete Excavation – used in firm subsoils. The Centre of the basement is
excavated first, then the basement slab cast while the sides of the excavation are
supported by struts
100
What are the 3 different types of basement construction?
Retaining wall and raft (monolithic) – consists of a slab raft foundation (basement
floor) that distributes the building loads, the basement walls are the retaining walls
Box and Cellular raft – similar to above but internal structural walls are used to
transmit and spread loads over the raft – divides the basement into cells
Piled – main superstructure loads are carried to the basement floor by columns and
transmitted to the ground via pile caps and bearing piles (i.e. your basement has a
whole load of columns going through it)
101
What is a rain-screen cladding system?
It is a cladding that manages the flow of rainwater on a building.
It is not necessarily waterproof itself, but more serves as a screen and protection
against rain for the rest of the building.
102
Under what conditions would you expect a raft foundation to be used
for a substructure?
A raft can be used for lightly loaded buildings on sites with poor soils
Heavy loads to the raft have the potential to cause the raft to move sideways as a
result of raft foundations not being very deep.
103
What is Type C tanking?
Drained Cavity System System accepts that a small amount of water will
occur through the monolithic
structure
Inner non-loadbearing walls and floors constructed to form a cavity
Water is then drained away to sump pump
The floor is composed of special triangular tiles
104
What do the Building Regulations do?
Made under the Building Act 1984. They are used to ensure the safety of people in &
around a building. Also used to promote energy conservation & comply with building
access requirements for the disabled. Define work covered & exempt from the BR &
set out procedures for notification, carrying out & completion of work & technical
requirements for compliance.
105
What is a U-value?
• Thermal transmission coefficient of an element.
• Lower the value the better insulated it is.
• Measured in W/m2k
• It is defined as the rate of heat flow in watts (W) through an area of 1 square
metre (m) for a temperature difference across the structure of 1 degree
centigrade or Kelvin (K).
• Covered by Building Regulations Part L
106
What is a scaffold?
Temporary working platform erected around the perimeter of a building or structure
to provide a safe working place at a convenient height
107
What are the advantages and disadvantages of steel frame and
| concrete frame?
Steel frame - Ads - Quick to erect, easy to produce, high strength to weight ratio,
delivered to site already fabricated, generally cheaper, light sections can be lifted into
place, monitor quality, effective use of space. Disads - Requires fire protection, rapid
cost increase/decrease, environmentally unfriendly.
Concrete frame - Ads - Flexible design allowing various shapes & does not impact on
the building layout, cash flow for contractor, fire performance. Disads - Higher cost
involved, skilled labour, takes longer, issues with monitoring quality on site
108
What are “reserved Matters” on a planning permission?
Approval of Reserved Matters is required following the granting of an outline
application.
A reserved matters application sets out outstanding details of the proposal including
access arrangements, siting, design and landscaping, while taking into account any
conditions that have been given in the original outline consent.
These comprise siting, design, external appearance, means of access and
landscaping.
109
How are fire barriers formed in a suspended ceilings and what
happens when services pass through the barriers?
If a suspended ceiling is not fire resistant, fire barriers will be required within the
ceiling void if the walls stop at the underside of the ceiling.
The barriers will be installed between the soffit of the floor above and the suspended
ceiling. In other words the ceiling void will need to be compartmented.
It is also important to consider whether smoke stops are also required.
When services run through the barriers it is important that they are sealed to prevent
fire spreading through the service gap.
110
What is formwork?
Anything that holds fresh in-situ concrete in place until it hardens, such as plywood
shutters, steel pan forms, fibreglass moulds or profiled decking, as well as its
supporting props, centering or falsework, plus accessories like wedges and clips for
tightening joints and to make stripping easy.
111
What is a Steel Table?
They provide standard information on steel sections in a tabulated form. For each
serial size and Universal beam number.
112
What items would you expect to find on a timber or part glazed door
that was required to have a half-hour fire rating?
3 hinges
Intumescent strip on door or edge of frame
Self-closing devise
If glazing panel is present it must be 6mm thick, wired glass to a max of 1.2m2 with
13mm x 13mm wood beads encased with non-combustible materials
113
What are CFA (Continuous Flight Auger)?
• Concrete is pumped into excavation simultaneously as the auger is
removed
• No need for temporary support
114
Building Regulations - can you commence on site without "plans
approval"?
Commencement on site may only go ahead once the reserved matters have been
achieved.
115
In a brick/block cavity wall, how are window openings dealt with in
terms of closing the cavity, preventing water penetration and
structurally?
Preventing Water Penetration
Cavity Tray – A damp proof course that crosses the 50mm wide cavity of a cavity
wall, stepping up at least 150mm between the outer and inner leaves, to form a
gutter that leads to a weephole in the outer leaf.
DPC – (Damp Proof Course) – A strip of impervious material the same width as
brickwork or blockwork wall to stop moisture rising from the ground up the external
leaf of the wall.
Structurally
Lintel – A small beam over a window or door head usually carry a wall load only.
116
What are the various ways of fire protecting frames? "Generic
materials such as brick, block, plaster
Cement/gypsum based sprays
Intumescent paint
Encasement with fire protection plasterboard / protection blankets
Concrete frames are self-protecting"
117
What are the different types of screed?
Bonded Screeds - Laid on to a ready prepared rough, cleaned concrete base
Unbonded Screeds - Laid on to a sound, clean Bitumen damp proof membrane to
BS4483
Floating Screed - Laid with steel or fibre reinforcements on to the insulating board,
which in turn can be laid on to a suitable damp proof membrane. Sound, clean
prepared base.
Resin Bonded Screed - Laid on to a clean, rough pre-prepared concrete base. The
resin acts as a ready installed damp proof membrane to the top screed.
118
What are the differences between precast concrete and in-situ?
Cost - PC tends to be cheaper - fewer ancillary costs.
Access - use of PC restricted by poor access.
Quality - PC - may be of poorer quality due to bulk manufacture off site"
119
What are the factors that might affect the choice materials for internal
partitions?
```
Fire rating requirements,
Restriction for noise (Db rating),
Visually – Opaque/Transparent
Fixed or movable
Strength - If anything is to be fixed to the wall
```
120
What are automatic fire sprinkers?
Automatic fire sprinklers are individually heat-activated, and tied into a network of
piping with water under pressure. When the heat of a fire raises the sprinkler
temperature to its operating point (usually 165ºF), a solder link will melt or a liquidfilled
glass bulb will shatter to open that single sprinkler, releasing water directly over
the source of the heat.
121
What is the difference between hard and soft landscaping?
Soft - turf, plants
| Hard - concrete, tarmac"
122
What is the maximum pitch of a flat roof?
Anything less than 10%
123
What is cold bridging?
◼ A component of high thermal conductivity extends through another building
element (e.g. metal fixings through insulation)
◼ It provides a passage for heat travel / loss
◼ e.g. lintels, wall ties, etc.
124
What are the requirements under Approved Document E?
Resistance to Passage of Sound
```
Pre-completion testing
Separating walls / internal walls
Separating floors
Dwelling houses and flats — change of use
Rooms for residential purposes
Reverberation in common parts e.g. flats
Acoustic conditions in schools
```
125
What are connections (in relation to steel) and what percentage would
you expect them to be?
Plates, bolts or welding. Usually 5% by weight.
What is an upstand?
A vertical strip or skirting, such as the weatherproofing where roofing meets an
abutment wall.
It can be the roofing itself, particularly for mastic asphalt, the top part of a one-piece
apron flashing, a mortar skirting or an upstand flashing, and either stepped, raking or
level.
126
Draw a King Post Roof
...
127
What are the procedures available for obtaining building regulations
approval?
2 types depending on the scale & nature of the works.
1) Full plans application - plans & construction details prior to starting on site, which
is reviewed by the LA/AI who will consult with stat authorities. May attach conditions
to approval. Approval lasts for 3 years from date of notice
2) Building Notice - Allows work to commence upon giving notice (Excludes work
with safety issues, a workplace or affects drainage)"
128
How do you remedy contaminated land?
◼ Excavate and remove offsite to designated landfill
◼ Encapsulate e.g. underground bentonite walls
◼ Treatment e.g. soil washing, bio remediation
◼ Planning - The Planning System provides a mechanism for remediating sites. e.g.
brown field site may require a Phase 2: Survey. May be a planning condition
◼ Insurance — Environmental insurance may be taken out to protect against costs. If
contaminated land is known about before insurance is taken out, then the policy will
be void
129
What are pad foundations?
Provide a base for reinforced concrete or steel columns
| Usually constructed from reinforced concrete
130
What is a raft foundation?
Used to spread the load of the superstructure over a large base and reduce the load
per m2 of the area
Useful in low bearing capacity soils and heavy individual column loads
Can be a solid raft slab or beam and slab raft – ground beam system and suspended
PC concrete ground floor
131
What is Heave and what are the signs?
• Opposite of subsidence
• Expansion of ground beneath the foundations
• Tapered cracking with cracks wider at the bottom than the top
• Basement floors convex and parallel cracks to the perimeters of the floor
• Clay soils expand (heavy rainfall, removed trees or leaking / damaged drainage)
• Clay board can be introduced to create a void under the floor
(biodegradable honeycomb void former, placed under floor slab. Leaves
void to accommodate heave)
132
Do you know any other types of frames?
Steel - Timber frame - Glulam - Reinforced concrete - Precast
133
What is post tensioned concrete?
This method is usually employed where stressing is to be carried out on site after
casting an insitu component or where a series of pre-cast concrete units are to be
joined together to form the required member.
In post-tensioning, concrete is cast around ducts or sheathing in which the tendons
are to be housed.
Stressing is carried out after the concrete has cured by means of hydraulic jacks
operating from one of both ends of the member.
134
What are temporary works?
Temporary works do not normally appear on construction drawings but demonstrate
methods that might be appropriate and resources necessary to ensure safe
construction i.e. propping.
135
What is shoring?
Form of temporary support given to existing buildings
| Purpose is to provide a precaution against damage or injury for collapse of structure
136
What is a metal grid ceiling – what are the benefits?
Suspended ceiling system formed by a square grid.
Quicker to construct.
Allows for service runs through the void above thus allowing greater floor to ceiling
height.
Easy access for service/repairs
Damaged tiles can be replaced rather than whole ceiling.
137
What are the advantages and disadvantages of the following flat roof
coverings: single layer membrane, built-up membrane system and
asphalt?
Single layer membrane – one layer of felt consisting of a base sheet of a base sheet
of glass fibre or polyester reinforcement impregnated with hot bitumen during
manufacture. It is then coated both sides with a weatherproof bitumen compound. It
is then dusted with sand on one layer and a thin layer of polythene on the other and
left to cool. After cooling it is cut into strips ready for use.
Built up felt – is constructed using three layers of the above felt. The first is laid at
right angles to the fall commencing at the eaves. The next is laid parallel to the fall
and the final layer at right angles. It is then covered with stone chippings.
Asphalt roofing – mastic asphalt consists of an aggregate with a bituminous binder
which is cast into block ready for reheating at site. They are heated into cauldrons to
a temp of 200 degrees C and are transported in liquid form to the roof. Two coats are
usually required.
Single layer membrane is too thin and are easily punctured are rarely used. But form
the cheapest option.
Built up felt is more common but can be easily punctured if proper care is not taken.
Asphalt roofs reduce risks of defects as it is poured on site rather than coming to site
in rolls which can be damaged in transport.
Asphalt cools quickly and will need to be heated close to the roof.
Heating anything to 200 degrees C is dangerous especially in a working
environment. Proper H&S drills need to be in place
Asphalt roofs are hard wearing and are design to allow for transit over them. Some
companies offer a 60-year guarantee on them.
138
Name some roof tiling materials?
Clay
Concrete (modern but heavy)
Slate
+ Typically, double lap but every tile is mechanically fixed
+ Most common is Welsh (grey blue colour)
+ Be wary of Spanish slates (not as hard wearing as UK and cheap)
139
What is power floated and why?
Concrete is power floated in order to maintain a flatter surface of lightweight concrete
that has been applied at a faster rate i.e. in commercial offices.
140
Are you aware of the RIBA Plan of Work?
Yes
It's a framework for use on projects with clients to provide greater clarity on project stages.
141
What stages of the RIBA plan have you been involved with?
All 0-7
142
What foundation types are you aware of?
Raft
Strip
Trench Fill
Piled
143
When might piled foundations be used?
In Clay or weak soil/ground to reach solid substrate.
144
What are the advantages of a concrete framed structure over a steel framed structure?
Inherent fire resistance
145
What building elements are classed as the super structure?
```
Works above ground level
Walls
Windows
Upper Floors
Roof
```
146
How might you tank a basement?
Retrofitted you can use a cavity drain system with a sump pump
147
What are the components of a timber pitched roof structure?
```
Rafters
Joists
Purlins
Strut (?)
Wall plate
```
148
How might an internal partition be altered to provide better acoustic performance?
Addition of acoustic insulation
149
Give me some examples of the different heating systems present in the properties you maintain.
Boiler?
150
What form of floor construction would you expect to find in a 1970’s purpose-built block of flats (to ensure sufficient fire protection?
I'd assume concrete but it's not something I work with
151
Explain the principles of compartmentation in relation to purpose-built blocks of flats
```
Fire Breaks
Fire Doors
Fire Alarms
Sprinkler systems (Above 11m)
Dry Risers (Internal pipework for access by firefighters)
```
152
Your case study project considered tanking, explain what types of tanking system were considered.
Actually considered waterproofing measures rather than tanking, so I would recommend cavity drain system with a sump pump as being most applicable as a retrofitted option (Type C)
153
William Stukeley
| Explain how the new extension was to be connected to the existing building.
Extension tie kits and box gutter. Designed to be seperate
154
William Stukeley
| Explain the construction of the new roof to the extension.
Trusses - pitched roof
155
William Stukeley
| What information was included on the sections?
Wall and floor construction section drawings
156
William Stukeley
| What type of foundations were designed for the new extension?
Piles
157
William Stukeley
| What services were provided to the new classroom extension?
Minimal, just electrics heating and internet/
158
William Stukeley
| How much insulation was specified for the external walls?
100mm
159
William Stukeley
| What was the external wall construction of the new extension?
Breeze block, facing brick and insulation. Traditional cavity
160
William Stukeley
| Why were piled foundations required?
Pile foundations to a depth of around 5m due to made ground and a soakway in the location of the extension
161
William Stukeley
| Why was steelwork required to support the pitched roof?
Structural Engineer didn't want the new roof connecting to the existing due to a concern of differential movement
162
William Stukeley
| Explain what advice you gave to your client regarding the construction.
I recommended traditional construction to with facing bricks to match the existing school due to the site being in a conservation area.
163
Garage Conversion
| What advice did you give on the suitability of the conversion?
Advised on access
sustainability
access for services
Planning requirements
164
Garage Conversion
| How did you recommend that the conversion would meet Building Regulations requirements?
Thermal upgrades to Part L1B
Fire safety Part B
Part F - Ventilation for kitchen and bathroom
Part P - Electrical Works
165
Garage Conversion
| What did you advise in relation to sustainability and energy efficiency?
Insulation to roof space, walls and floors
166
Garage Conversion
| How did you suggest that the conversion would comply with Approved Document B?
Ensured a heat detector was installed within the kitchen
| Window to front elevation was an escape window.
167
What is the U-value for floors?
0.22
168
Garage Conversion
| What was the existing roof structure and what works did you recommend to this?
Pitched roof
| Addition of 250mm roof insulation at ceiling level
169
Garage Conversion
| How did you advise that insulation would be installed to the floors and walls?
130mm insulation to floor with DPM and chipboard floorboards
| 60mm board insulation fixed to battens internally.
170
Garage Conversion
How did you propose that a bathroom, kitchen and bedroom would be squeezed into an old garage space? Was the garage a double or single?
Large single garage with alleyway between existing house and garage
New en-suite to alley and kitchenette single bedroom within the garage.
171
Garage Conversion
| What were your recommendations for drainage from the bathroom?
There was an existing foul drainage run next to the garage that was connected into. Drinking water connections were taken from the adjacent kitchen.
172
Garage Conversion
| What were you recommendations regarding ventilation?
Extractor fan to the kitchen and bathroom
173
How do ground conditions influence design?
Clay soils may require a raft foundation or piles. Can also influence design due to risk of differential movement.
174
Name a product you specified for William Stukely School and Why?
Ancon stainless steel wall ties
| Rockwall Full Fill Insualtion Batts
175
Why did you choose a 1200 guage DPM?
1200 guage details the thickness. This prevents moisture from penetrating the slab from the ground but
176
Why did you use Rockwall Full Fill insulation batts?
To achieve 0.28 u value (lower as extension to non domestic)
| Rockwool full fill is easier for builders to install and less prone to poor workmanship.
177
How much insulation did you install in the garage conversion?
300mm
| between and over joists to reduce cold bridging
178
How much insulation did you use on the internal walls?
60mm Kingspan Kooltherm insulated plasterboard
179
How much floor insulation did you install>
130mm Kingspan thermafloor
180
What u value does a floor have in the UK?
0.25
181
What mix did you use for the screed?
1 part cement to 4 parts sand
| BS 12
182
Which approved document deals with insulation?
Part L
183
How often were the tiles nailed into the battens on the roof?
Every tile fixed using galvanised nails. As per manufacturers requirements, can vary dependant upon tile and building location.
184
What are the positives and negatives of concrete framed buildings?
```
Heavy so require deeper foundations
Not very carbon friendly
good fire resistant properties
good sound resistance
durable
```
185
What are the positives and negatives of steel framed buildings?
quick to erect
got to be precise when installing
durable
insect resistant
186
What are the different stages inspected by the Building Control officer?
```
Foundation
DPC
Floor slab
drainage
floor joists
roof
```
