Condensation

Question 1

Condensation occurs when…

Answer 1

moisture can no longer be maintained as vapour within the air.

Question 2

Damages it causes

Answer 2

• mould growth
• damage decorations and fittings
• corrosion and decay of the building fabric and in severe conditions it may even lead to structural failure
• reduction of thermal resistance

Question 3

Health problems

Answer 3

prolonged dampness can cause the proliferation of a number of fungal bacteria.
can cause:
- respiratory infections
- allergic diseases
- irritative and non-specific symptoms
- other chronic pulmonary diseases

Question 4

Source of moisture for condensation

Answer 4

• building occupants - sweating and breathing
• cooking
• clothes washing
• clothes drying
• industrial processes

Question 5

why does condensation occur?

Answer 5

moist air comes into contact with a surface that has a temperature below the dew point,
Or too much moisture for the given air in contact with the surface
Or too low a surface temp for given moisture

Question 6

Interstitial condensation

Answer 6

occurs within or between the layers of the building envelope

Question 7

Surface condensation can be controlled by:

Answer 7

• reducing the generation of moisture
• increasing ventilation
• more insulation - increase surface temp
• increasing heat input - increase surface temp