Natural Ventilation Advice

Natural Ventilation Advice - How to improve your indoor air quality, to breathe a little easier and cleaner.

The following article provides you with natural ventilation advice, how to use simple methods to increase the air quality in your home.

Natural, fresh outdoor air and constant ventilation is vital in your home. Modern buildings can be air tight which limits fresh air entering your interior, causing stuffy 'dead' rooms, lack of concentration, lethary and fatigue.

The fastest and simplest way to refresh the air in your home is by regularly opening the windows and the doors. This is known as air exchange (indoor air exchanging with outdoor air). Close your windows in the hot summer months and open them at night to keep your home at a cooler temperature than outside. Winter is difficult for a lot of locations, most people shudder at the thought of opening their windows and doors. A quick 5 minute blast of fresh air won’t affect the overall temperature in your home by too many degrees. When less cold temperatures arrive, start opening the doors and windows a little more. Opening windows and doors is free and very effective!

Effective natural ventilation helps dissipate indoor air pollutants, moisture and lingering odours. This increases the quality of the air which is of benefit to your health short and long term. Natural ventilation creates a more comfortable home and environment to live in.

Poor ventilation allows contaminants such as VOCs to reach high concentration levels. Sources of indoor pollution are from building materials, surface finishes; paint, floor coverings and furniture, furnishings, electrical items, household cleaning products and any burning substances; smoke, candles, fires. The downside of natural ventilation is that outdoor air pollutants from nearby traffic or your own car emissions from the garage can enter the house.

Traditionally natural ventilation occurs through gaps and cracks found in the wall materials, floor coverings, vents, windows and doors. The amount of ventilation is known as the infiltration rate. This rate is determined by the season, climate, age and construction methods of your home which makes it difficult to control. There is a fine line between high and low infiltration rates – which either lead to high levels of indoor pollutants or increased energy costs from too much ventilation and the systems used to compensate.

Basic methods of ventilation are the use of ceiling fans, extractor fans (bathroom, kitchen, WC, garage), air vents – more structural methods are the orientation of your building and wind chimneys.

Natural ventilation advice - Cross ventilation

Opening separate doors and windows creates cross ventilation which helps exchange the air quickly by creating draughts that pull stale air through your home to the outside whilst drawing in fresh air into the room. This method makes use of high and low air/wind pressure. Advanced methods of cross ventilation will look at the orientation of your house and the position of doors and windows.

Natural ventilation advice - The stack effect and ventilation

How does air circulate around your home? Air expands when it gets warm and rises upwards (high air pressure) – when it starts to cool it descends (low air pressure). This is an ever circulating cycle in air tight rooms in your home and is known as convection. Think of this cycle in relation to the whole house.

Warm air rises to the roof and goes out of the building through gaps and cracks into the air outside – simultaneously cooler air is sucked into your home through gaps and cracks in the cellar or ground floor. This vacuum caused by warm air leaving your home is known as the chimney or stack effect. It is the same effect when you have a chimney, drawing up smoke from your open fire into the air outside. Your home can be designed to have a vent or opening near ground floor level and one at the top to aid the stack effect. This can also be achieved in each room.

Advantages

• Efficient method of ventilation – air has an easy route to escape.
• Effective and entirely natural ventilation during the summer months.

Disadvantages

• Unless planned into the build and controlled the disadvantages outweigh the advantages.
• Creates draughts.
• Too much warm air can escape, losing heat.

Natural ventilation advice - Building Materials

The building materials that were used to build your home play a vital role in ventilation. Flooring, walls and ceilings must be made of materials that can breathe and allow air to circulate through them – without heat loss. The majority of synthetic materials do not allow your home to breath. An example of this is paint; chemical based paint provides a plastic covering over your walls – opposed to natural paint which is micro porous and allows air flow to travel through to the wall beneath. Now consider the wall material e.g. stud work or plastering, do these materials allow air through?

If you would like more natural ventilation advice for your home please contact us.