Construction Technology and Environmental Services

Question 1

What are the 5 phases of construction projects?

Answer 1

1. Project inception.
2. Pre-construction design.
3. Procurement.
4. Construction.
5. Post Construction.

Question 2

What is the meaning of ‘Modern Methods of Construction’

Answer 2

The use of innovative and off-site manufacturing techniques to construct buildings. e.g. precast panels and foundations.

Question 3

What is the meaning of ‘traditional’ methods of construction?

Answer 3

Traditional methods of construction relate to on site building processes.

Question 4

What are the benefits of modern methods of construction?

Answer 4

Cost effective.
Sustainable.
Precise.
Reduced waste.
Better quality control.
Allows for streamlined construction.

Question 5

What are the benefits of traditional methods of construction?

Answer 5

Allows for more flexibility for onsite changes.

Question 6

What are the drawbacks of traditional construction methods?

Answer 6

Traditional construction relys on onsite labour and materials which can often lead to inefficiencies and delays.

It is also suceptible to weather conditions and inconsistencies in quality.

Question 7

What is a septic tank?

Answer 7

A septic tank is a buried, watertight container that holds wastewater and partially treats it.

A septic tank has two main elements.
1. The underground tank.
2. A drainage field.

Question 8

How does a septic tank work?

Answer 8

The raw sewage flows into the tank where it then seperates into three layers; scum, sludge and effluent.

The effluent is the liquid wastewater which exits the tank and travels into the drainfield for further treatment.

The drainfield is a shallow excavation in unsaturated soil that allows the wastewater to filter through the soil and disperse into groundwater.

Question 9

For the rural house in chorleywood, which septic tank did you use and why?

Answer 9

As the property was a 6 bedroom house, it required a 4000 litre septic tank, and one from the Klargester brand was chosen.

Question 10

What is substructure?

Answer 10

The elements below the DPC, that provides the base for the superstructure to be constructed on.

Question 11

What are British Standards?

Answer 11

They give recommended minimum standards for materials, components, design and construction practices.

Question 12

What is a superstructure?

Answer 12

All internal and external work items above the damp proof course, which are made up of:

External walls, stairs, roof, structural walls, suspended ceilings, raised floors.

Question 13

What are site investigations for and what is included in them?

Answer 13

The objective is to collect and record data to help with the design and construction process including matters that may impact the development.

Boundary hedges & fencing.
Existing trees
location and size of services
existing buildings
ground water conditions
soil investigations
trial pit info

Question 14

What isthe purpose of soil investigations

Answer 14

To determine the suitability of the site for the proposed works and determine adequate and economic foundation design.

The investigation should determine the potential difficulties associated with the ground conditions and assist with identifying a suitbale foundation solution.

Question 15

What is shoring?

Answer 15

A form of temporary support given to existing buildings.

It provides precaution against damage or injury due to collapse of the structure.

Question 16

What are the main components of concrete?

Answer 16

Water, cement and aggregate.

Question 17

What are the different types of piles?

Answer 17

Sheet piles.

Secant piles (interlocking)

Bored (auger) piles.

Precast driven piles.

Question 18

When are piled foundations most suitable?

Answer 18

On shrinkable clays or in areas with new or felled trees.

Where a firmer layer of ground is at considerable depth, i.e. where strip foundations would be uneconomical.

Where the water table is close to the surface.

Question 19

When are strip foundations most suitable?

Answer 19

On rock, gravel dense sand or stiff clay (narrow strip foundations are common).

On soft clay or soft sandy clay. (Wider strip foundations are required)

Question 20

When are raft foundations most suitable?

Answer 20

On grounds with low bearing capacity, such as soft clay or silt.

In mining areas, where subsidence is a risk.

On deep areas of fill, where piling would be uneconomical.

Question 21

What are the technical advantages of steel frame?

Answer 21

Quick to assemble.

Lighter than concrete which can mean a cheaper foundation method.

100% recyclable.

Highest strength to weight ratio.

Do not expand or contract depending on wether conditions.

Question 22

What are the disadvantages of steel frames?

Answer 22

Require fire protection to be retrospectively installed.

Price of steel fluctuates and can result in a lack of certainty.

Specialist builders required.

Question 23

What are the technical advantages of a conrete frame?

Answer 23

Fire protection is often part of the structure.

The initial constrcution is slow, so can result in reduced cashflow expenditure early on in the development.

Maintenance requirements for concrete frames are relatively low.

Can provide good sound and heat insulation in comparision to steel.

Question 24

What are the technical disadvantages of concrete frames?

Answer 24

They are more time consuming to install, than steel frames.

The weather conditions during installation can also slow down construction.

The need for steel reinforcement can lead to issues with price fluctuations and therefore price uncertainty.

They are heavy and require larger foundations.

Question 25

Describe a typical Cold Flat Roof Construction.

Answer 25

A flat roof with a ‘cold roof’ construction is formed with the insulation located above the ceiling and between the timber roof joists.

There is an air gap above the insulation to allow for cross ventilation to reduce the risk of condensation.

A timber deck is placed above the joists and then finished with the water proofing system.

Question 26

Describe a typical warm flat roof construction.

Answer 26

A roof with a ‘warm roof’ construction is formed with the waterproof system, on top of the insulation, on top of the vapour control layer, on top of the roof deck, which is placed on top of the roof structure.

Question 27

What is an inverted flat roof?

Answer 27

A roof where the insulation is placed on top of the waterproofing roofing system.

The insulation protects the roofing system from damage.

Question 28

Describe a typical parapet wall and roof abutment detail.

Answer 28

The parapet wall is built along the perimeter edge of the roof, but extends above the roof level.

Where the wall intersects with the roof, a flashing or water proofing detail will be required along with a DPC closer placed above the flashing and at the head of the wall under the coping detail.

Question 29

Describe a pitched roof detail.

Answer 29

Pitched roofs are typically made up of rafters which span from the apex of the roof and are fixed to the top of the external wall by a wall plate.

The roofs are typically supported by purlins, struts and roof beams.

The roof is weathered with a breathable membrane, laid horizontally across the slope, with slack between rafters. The membrane should be lapped by at least 100mm.

Over the membrane, timber roofing battens are installed with the final roof covering over the top and finished with ridge tile to the apex.

Ventilatiion should be provided within the soffits, slopes or at the ridges to allow natural ventialtion.

Question 30

What is rainscreen cladding?

Answer 30

It is a type of exterior panel system that protects a building’s wall from the elements while also improving its thermal performance and appearance.

Question 31

What is a curtain wall system?

Answer 31

A modern architectural method for creating glass façades.

Question 32

What are the different part of a steel beam?

Answer 32

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 beam.
Root - where the flange and web join.

Question 33

What is intumescent paint?

Answer 33

Fire resistant paint. It works by stopping oxygen from reaching the surface of the material is is protecting.

Question 34

What is formwork?

Answer 34

Anything that holds fresh in-situ concrete in place until it hardens, such as plywood shutters.

Question 35

In a brick block cavity wall, how are window openings dealth with in terms of preventing water penetration and structurally?

Answer 35

To prevent water penetration:
Cavity trays are used which cross the cavity and form a gutter that leads to a weephole in the outerleaf.
A DPC is installed to stop moisture rising up through the external leaf of the wall.

Structurally:
Lintels are used to carry to the load from above.

Question 36

What is the size of a standard brick?

Answer 36

215mm x 102.5mm x 65mm

Question 37

How many bricks are in a m2

Answer 37

Approximately 60 bricks per m2.

Question 38

What are the different types of brick bond?

Answer 38

Stretcher or english.

Question 39

What factors might affect the choice of materials for internal partitions?

Answer 39

Fire rating requirements.
Acoustic requirements.
Visual requirements.
Strength requirement.

Question 40

What are the different types of screed?

Answer 40

Bonded screed - Laid on to a prepared concrete base.

Unbonded screed - laid onto a clean bitumen DPM.

Floating screed - laid with steel or fibre reinforcements onto the insulation board.

Resin bonded screed - laid onto a prepared concrete base. The resin acts as a DPM to the top screed.

Question 41

What are the elements of a flat roof?

Answer 41

Joists.
Firrings.
Deck.
Roof covering.

Question 42

What is a syphonic drainage system?

Answer 42

It is an alternative to the gravity system.

Water is sucked from the guttering in to the drain pipe so there is no need to have pipes set at a gradient. A vaccum is created to achieve this.

It has the advantage of that narrower pipes can be used.

They are normally used on large industrial buildings where grvaity systems are not efficient.

Question 43

How are fire barriers formed in suspended ceilings and what happens when services pass through the barriers?

Answer 43

Fire barriers are installed between the soffit of the floor above and the suspended ceiling, resulting in the ceiling void being compartmentated.

It is also worth considering is smoke stops are required.

Services should be sealed to prevent fire spread.