Tooltip Tags: ventilation

Dew point

Dew point is the temperature below which the equilibrium between evaporation and condensation is tilted towards condensation, i.e. condensation starts to form.

Dew point is also a proxy the vapour pressure. Comparing the dew point of one area to another makes it possible to see where vapour is being generated or conversely removed (normally through ventilation).

TIP: cooker hood ducting

Cooker hood ducting. Consider instructing a general builder to install an external ducting from your cooker hood using ridged ducting.

TIP: flexible ducting

Flexible ducting. Consider instructing a builder to replace the flexible ducting with a 100mm ridge pipe. Consider ducting straight out.

TIP: install an externally ducted kitchen

Install an externally ducted kitchen extractor fan with rigid ducting, either above the hob, or light switch operated. Hoover HGM600X (£149) has a Which! Best buy.

TIP: kitchen ducting

Kitchen ducting. Instruct general builder to duct out kitchen extractor fan (use rigid ducting and cut a circular or rectangular hole (flats may require freeholder permission).

Relative humidity

Relative humidity is defined as the measure of how much vapour is in the air compared to air’s capacity to hold vapour – expressed as a percentage.

It is a function of vapour pressure (quality of vapour) and temperature. As temperature rises, air can hold more vapour.

Conversely as temperature drops, air holds less vapour until it meets the dew point at 100%RH, when dew or condensation forms.