Archive for February, 2011

Black Mould

Monday, February 14th, 2011

Black mould can be a constant source of distress to many homeowners.

It is especially common in older properties, which are poorly insulated and ventilated and which have been ‘modernised’ to provide central heating and showers, draught stripping and double glazing.

Black mould on cold surfaces

Black mould normally occurs due to condensation; that is where warm, moisture-laden air condensates on cold surfaces creating a damp environment in which the mould can grow.

Bathrooms, bedrooms and kitchens are the most common rooms to suffer and small bungalows or big old houses can suffer in equal measure.

There is no single cure.  Each incident must be considered on its merits but the main requirements are:

  1. Good extract ventilation to remove the moisture laden air quickly
  2. Good insulation to prevent wall surfaces from getting too cold
  3. Good heating to warm wall surfaces

A common fault is that bathroom fans are often undersized or linked to the light switch.  This is a mistake, they need to be sized to extract the steam quickly, not just to provide background ventilation and they need their own switch so they can operate when the light is switched-off.

Bathrooms should also be ‘overheated’.  Don’t be afraid of installing a large heated towel-rail radiator and make sure it’s free from any thermostatic controls.

For further information and advice contact Chris Mills on 01332 603000.