Expert’s Guide Ventilation for Bathroom and Toilet
New building materials and construction methods are effectively resulting in “waterproof” buildings.
They trap moisture inside just as effectively as they keep moisture out.
Open doors and windows provide air circulation and ventilation but security considerations mean that
we are increasingly less likely to use this option. Houses tend to remain closed up more and more.
Problems Caused by Poor Ventilation
Stale air can be caused by cooking smells, odors remaining in the bathroom, a general lack of ventilation around the house as well as a damp atmosphere.
All these problems cause an avoidable level of discomfort as well as the risk of respiratory illness and general poor health.
Problems also occur when steam from the kitchen or bathroom finds cooler surfaces around the house on which to condense. Warm, moisture-laden air condenses on cold surfaces such as glass, cold ceilings and cold wet-wall linings. This is the moisture that you can see.
Moisture you cannot see is still present in the atmosphere and will be absorbed into fabrics, wall linings, bedding, etc. Attempts to conserve heat by sealing windows – and therefore reducing natural ventilation – makes this problem even worse.
Condensation can cause considerable problems from peeling wallpaper and mould growth to severe long term structural damage to building materials .
Forced and Natural Ventilation Guide
Natural Ventilation for the above is acceptable as long as opening windows in each room have an area of 5% or more of the floor area of the room.
Where fans to remove moisture and other contaminants from kitchens, bathrooms and laundries
in housing, we duct the exhaust air to the outside at the flow rates mentioned above.
For example: A bathroom is good at between 11 & 15 air-changes per hour. Therefore 15 changes per hour means the total air preplace in the room after 4 minutes.
Eg (60 minutes @ 15 changes per hour = 4 minutes) This would mean an average bathroom usage of 12. 16 minutes resulting in the total air volume to change 3 to 4 times. Thus, this equates to a rate of 15
ACH. This is Expert’s Guide Ventilation for Bathroom and Toilet!
