Posted on 08 10 2020

How To Choose A Ventilation System For Your Home

Condensation and excess moisture levels in a home can be a breeding ground for mould, bacteria, and mildew. By controlling the amount of moisture in your home, it will be easier to heat, save you money on your power bills, and make it healthier.

Adequate ventilation helps control moisture levels and is a critical part of creating a healthy environment, but it can be hard to know where to start when it comes to choosing the right ventilation option for your home. We’ve put together these simple steps to choosing the right option:

1. Check your heating and insulation

Before upgrading or installing a ventilation system, it is essential to check the basics like heating and insulation. Ensure you have a decent heat source in your home, such as fixed, efficient sources of warmth like heat pumps or wood burners in living areas, and in smaller rooms, energy-efficient heaters. Where possible, you should also make sure both floor and ceiling insulation is installed.

2. Identify and eliminate sources of moisture

Some sources of moisture are generated from within the home itself, so identify and target the areas of your home where the most moisture is generated, such as your bathroom and kitchen. Consider adding a shower dome, and install high-quality extractor fans into your bathrooms and kitchen.

It also pays to get a professional to check for any rising damp, fit a plastic moisture control sheet if necessary, and regularly check for any blocked drains that could cause water to pool under the home.

3. Evaluate automatic ventilation systems 

Once you’ve taken the obvious steps to reduce moisture in your home, installing an automatic ventilation system is a great way to minimise moisture in the home further, and will be more cost-effective in the long run than cheaper solutions such as dehumidifiers. 

The system that will work best will depend on the specifics of your home, including the size, location, amount of sun it gets, the type of roof, and the local climate. As well as what you want to get out of your automated system, including any special features you want to be included.

4. Positive pressure? Balanced pressure? Heat transfer?

When you first start looking at automated systems, there is a lot of jargon to understand. Usually, the first thing to decide is whether to choose between a positive pressure or a balanced pressure system… neither of which compares to a heat transfer system (see point 6).

Positive pressure (also known as forced air) systems work by blowing drier air into your home from either the roof space above the ceiling or outside. They are best suited to homes with dry roof spaces, and older styles houses with wooden joinery where air can move past doors and windows, instead of modern sealed aluminium joinery, unless additional vents have been fitted. Additional heating will probably be required when using a positive pressure system during winter, if you live in a cold climate, or if your roof is very shaded.

Balanced pressure (also known as a heat exchanger) systems extract warm, damp air from living spaces and pass it through a heat exchanger to heat dry air, which the system brings in from outside. They are best suited to modern, airtight homes, and don’t have the same unintended cooling effect as positive pressure systems. 

5.  Don’t forget to check your filters

As most ventilation systems filter the air passing through them, it is important to consider the filter grade that they use. There are many filter types available, usually identified by a letter and a number (for example, G4). Generally, ‘F’ filters remove smaller particles than ‘G’ filters that will catch finer dust and smaller airborne bacteria. The higher the second number, the more effective the filter – so a G7 filter will be more effective than a G6 filter. There are also specialised and advanced filters available such as carbon filters to remove odours, HEPA filters for allergens, and so on.

6.  Think about heating

Some systems offer the ability to add heaters to ducting, which can help regulate temperatures if cold air is introduced from the roof space in winter, or cooling options are required in summer. 

If you have a good heating source in your main living area (such as a wood burner), which heats the space very efficiently but not the rest of your home, then installing a heat transfer system may be what you need.

By transferring excess heat from the main heating source to other targeted areas of your home, such as bedrooms or a rumpus room, you can achieve a more even temperature throughout your home. As a result, this will reduce overheating in your main living area, making it a more comfortable place to relax and entertain.

When it comes to ventilation and heating, our friendly home energy assessors can offer best practice advice on controlling the environment in your home to ensure that condensation, excess moisture, and unwanted odours are minimised, while promoting the benefits of air purity, warmth, and overall home health.

The first step is to contact us to book in your home energy assessment!


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