Construction Tech & Enviro Services

Question 1

What are the options for basement waterproofing?

Answer 1

Type A System: Barrier Protection
Type B System: Structural Integral Protection
Type C System: Cavity Drainage System

Question 2

What is a Type A System?

Answer 2

A Type A system uses a barrier protection geo-synthetic method typically applied during construction. E.g Bonded sheet membrane, liquid applied system, cementitious systems and crystallization powders and slurries.

Three methods of application: External Applied, Sandwiched or Internal Applied.

Question 3

What defects are associated with a Type A system?

Answer 3

Often the barrier protection is not accessible making inspect and repair difficult. Poor workmanship or inappropriate use of materials. A land drain no higher than the ground slab must also be installed (as per BS8102) to take away any residual moisture coming to bear against the structure. Clay soils often create a perched water table and put the structure under hydrostatic pressure.

Question 4

What is a Type B System?

Answer 4

Type B systems rely on the structural integrity of the construction materials typically watertight concrete with a free water content at 0.45 or below.

Low permeability concrete with good joint detailing.

Question 5

What defects are associated with a Type B System?

Answer 5

Water vs cement ratio during construction mixed incorrectly causing the following:

• Honeycombing
• Thermal Cracks
• Shrinkage Cracks

Question 6

What is a Type C System?

Answer 6

A type C system is known as a cavity drainage protection. Type C doesn’t resist hydrostatic pressure like a type A & B but provides protection via water management using drainage channels and pumps.

Question 7

What defects are associated with a Type C System?

Answer 7

Poor installation and workmanship. Poor lapping of membrane at floor joint. Pumps must be maintained with regular servicing to avoid flooding and failure. Free lime build up can block channels and cause failure to pumps.

Question 8

What is a cohesive soil?

Answer 8

Soil that bonds together i.e doesn’t let water pass e.g Clay.
Chalk is relatively free draining although generally cohesive.

Question 9

What is a less cohesive soil?

Answer 9

Soil doesn’t bond together i.e sands, gravels.

Question 10

What legislation governs basement waterproofing?

Answer 10

BS 8102 - Code of Practice for the Protection of Below Ground Structures against water from the ground.

Question 11

Where would you specify a Type A System?

Answer 11

New Basement Construction
Car Parks
Retaining Walls
Podium Decks

Question 12

Where would you specify a Type B System?

Answer 12

New Basement Construction 
New Underground Structure 
Lift Pits 
Tunnels 
Swimming Pools

Question 13

Describe the impact and possible defects from having air conditioning within a property?

Answer 13

??

Question 14

Name 3 types of Air conditioning systems?

Answer 14

Variable Refrigerant Flow (VRF)
Four Pip fan Coil
Variable Air Volume (VAV)

Question 15

What is the difference between comfort cooling and air conditioning?

Answer 15

Comfort cooling system provides cooling when required. Air Conditioning system controls humidity, heat and cooling.

Question 16

What is a VRF system?

Answer 16

A variable refrigerant flow system allows for individual heating and cooling by varying the refrigerant flow in individual areas so suits offices with different rooms, meeting rooms etc.

Question 17

What is a VAV system?

Answer 17

A variable air volume system works by variable the airflow in a building at a constant temperature. The air temp stays the same but the air volume varies. Requires large external condensing unit.

Question 18

What are the three fire alarm categories?

Answer 18

M= Manual 
P= Protects the Building
L= Protects Life (5 categories of L)

Question 19

What are the differences between the systems?

Answer 19

M= Manual - relies on the occupants to raise the alarm
P= Alerts emergency services to protect the building 
L= Protects Life - relies on automatic detection and call points

Question 20

What type of system was installed at 7 West Nile Street?

Answer 20

L2 Category System with automatic detection designed to protect lifes with sensors placed in high risk areas e.g kitchens and escape routes and routes adjoining escape routes.

Question 21

What is a ‘first fix’ construction stage of a construction project?

Answer 21

Electrically it is the install of containment routes and back boxes, the pulling through of cabling which is left exposed until second fix.

Mechanically it is the install of ductwork or pipework usually in concealed voids.

Question 22

What is a ‘Second Fix’ of a construction project?

Answer 22

Electrically it is making off of cable connections, install of light fittings and switches.

Mechanically it is the mounting of radiators, sprinkler heads and ventilation grills.

Question 23

What do you know about Modern Methods of Construction?

Answer 23

Modern methods of construction is an innovative way of constructing which involves either offsite manufacturing or onsite based technologies.

Question 24

What is volumatic construction?

Answer 24

Volumatic construction involves the construction of units within a factory that are connected to foundations onsite. These can include full pods complete with internal finishes and transported to site as a complete entity.

Question 25

What is panellised construction?

Answer 25

This involves the construction of panels onsite which are transported to site for assembly. Open or closed systems, closed systems can include windows and doors.

Question 26

What is hybrid construction?

Answer 26

Method which is a mixture of both volumatic and panellised construction.

Question 27

What are the onsite MMC methods?

Answer 27

These include construction using sustainable and innovative products such as use of Polystyrene blocks as formwork or aircrete planks.

Question 28

What is cladding?

Answer 28

Component that is attached to the primary building structure to create a non structural external facade.

Question 29

What is rainscreen cladding?

Answer 29

Double leaf system which carrys no structural load. The inner leaf provides thermal insulation and outer leaf protects against elements.

Question 30

What is ACM Cladding?

Answer 30

Aluminimum composite cladding panels consist of aluminimum bonded with lightweight material such as Polyethelene or Polyutherane.

Question 31

What legislation governs Cladding?

Answer 31

BS8414 - Fire Performance of External Cladding Systems.

Question 32

What does the technical handbook state?

Answer 32

Section 2 Fire (2.7) states that cladding to buildings must be of non combustible material. High rise buildings over 18m must be constructed of non combustible materials. As per euroclass could be A1 or A2.

Question 33

What are the Euroclass fire ratings?

Answer 33

A1 & A2 - non combustable
B-D - Limited to medium contribution to a fire
E-F - Significant contribution to a fire

Question 34

Steel vs Concrete

Answer 34

Steel has less construction time onsite and less requirement for wet trades. Concrete will be cheaper but has a higher Carbon Footprint.

Question 35

What are the design implications of Steel vs concrete?

Answer 35

Steel can span larger spans , concrete is more flexible in design.

Question 36

What are the time implications of Steel vs Concrete?

Answer 36

Concrete construction is faster than steel.

Question 37

How are steel protected against fire?

Answer 37

Thin intumescent coatings.
Thick epoxy coatings
Encasement
Blankets.