Sem 2 - Ventilation

Question 1

What part of the building regulations deals with Ventilation

Answer 1

Part F

Question 2

What building has a BREEAM outstanding for excellence

Answer 2

One Angel Square, Manchester

Question 3

What is infiltration

Answer 3

Infiltration is the unintentional or accidental introduction of outside air into a building, typically through cracks in the building envelope.

Question 4

What are the two main drawbacks to cross ventilation

Answer 4

Not appropriate in noisy polluted environments and opening windows in winter wastes energy.

Question 5

Air permeability is measured in what.

Answer 5

m3/m2h@50pa

Question 6

Units in Air Changes per Hour (ac/h); 1 litre/sec is equal to

Answer 6

3.6m3 / hour or 3600 litres per hour

Question 7

What are the two types of natural ventilation

Answer 7

• Cross Ventilation
• Stack Ventilation

Question 8

What are the three different types of ventilation

Answer 8

Natural, mechanical and mixed mode.

Question 9

What are the three units of measure fro ventilation

Answer 9

litres per second (l/s), cubic metres per hour (m3/h), air changes per hour (ac/h)

Question 10

How do we achieve the passivehaus standard in the UK

Answer 10

• Accurate design modelling using the PHPP (passive house planning package)
• High levels of insulation
• High performance windows with insulated frames
• Airtight building fabric
• Thermal bridge free construction
• A mechanically vented system with high heat recovery efficiency

Question 11

VAV is an air conditioning system but what does it stand for.

Answer 11

Variable Air Volume.

Question 12

Cross ventilation is a natural ventilation. What is it.

Answer 12

Naturally vented building is windows open on either side.

Question 13

What is a very tight building envelope in terms of air changes per hour

Answer 13

0.15 to 0.05

Question 14

What is the requirement for air change within a 24h period

Answer 14

0.3 air changes per hour

Question 15

Stack ventilation is a natural ventilation. What is it.

Answer 15

similar to cross ventilation, windows open on either side of building with a atrium funnel in the centre, fresh cool air enters the building whilst the warm air rises and escapes through the top of the atrium.

Question 16

What can drastically reduce heat loss from a building

Answer 16

Airtightness

Question 17

What is the minimum air change rate per 24H period

Answer 17

0.3 air chages per hour.

Question 18

What is the calculation for ventilation heat loss

Answer 18

Volumetric heat capacity of air (J/m3K) x infiltration rate per room (No. air changes per hour) x volume of room (m3) x temp diff between inside & out / 3600

Answer in units is Watts

Question 19

What does CAV stand for

Answer 19

Constant Air Volume

Question 20

With regards to air changes, 1 litre / second is equal to what

Answer 20

3.6m2 / hour

Question 21

What is Ventilation

Answer 21

It’s the deliberate process of replacing air in a space to maintain air quality. It can be minimised but not eliminated.

Question 22

What is the main characteristic of the CAV system

Answer 22

Volume of supply air constant but temperature varies

Question 23

50pa is equal to what

Answer 23

A 20mph wind.

Question 24

What are the two different types of natural ventilation

Answer 24

Cross ventilation and stack ventilation.

Question 25

When we speak about air leakage, we refer to what.

Answer 25

Air permeability

Question 26

What is the maximum air leakage rate for new buildings.

Answer 26

10m3/m2h@50pa or 0.5 air changes per hour at normal pressure.

Question 27

Ventilation is needed to maintain good air quality but also to remove.

Answer 27

Odours, mould, excess humidity and volatile organic compounds.

Question 28

What are the two types of air conditioning systems

Answer 28

CAV & SAV

Question 29

What is the main characteristic of the VAV system

Answer 29

Temperature of the air supply constsnt but volumes varies

Question 30

What building has an excellent example of cross ventilation

Answer 30

The Gherkin, 30 St Mary Axe, London