When it comes to designing a house that will be cool, comfortable, and healthy for the residents who live there, proper roof ventilation is a priority. Without it, a house will be too hot in summer, too cold in winter, which will lead to the owners having to jack up their energy bills. There’s also the danger of toxic mould if moisture is not ventilated correctly from the roof space.
With plenty of options on the market, it can be hard to know which roof ventilation solution is the right one for the project at hand. As you know, every house is different, which means every house has unique ventilation challenges and requirements.
The good news is, determining the optimal ventilation strategy for your project is an easy job if you follow the right process. In this guide, we will be outlining the calculation process and how to choose the proper roof ventilation.
How To Calculate A Property’s Ventilation Needs
Before we dive into the calculation, it’s essential to understand what an air change is. If you are not familiar, an air change is how many times the air in a room enters and exits in an hour. Generally, the more air changes you have, the better the performance of your ventilation and the healthier a house will be.
When it comes to attics in Australia, 10 air changes is usually enough if a roof is not exposed to significant moisture. For those who are in high-moisture areas, aim for slightly more air changes to accommodate for the difference in the environment.
If you want to calculate the number of air changes that your roof needs, you can use the air changes formula:
What you want to do is half the height of the roof and multiply that by the length of the roof and by the width of the roof. After that, multiply the figure you get by 10, and that will reveal your roof’s minimum air change requirement.
You can then use this figure when designing an air ventilation strategy and to assess the potential ventilation system on the market.
As a general rule, it’s a good idea to consider using a mix of powered and passive ventilation such as fans and vents as this will provide the best airflow performance in most situations.
If you want a completely passive solution that will maximise airflow and significantly reduce the energy costs of the property, then we highly recommend our award-winning product RapidRidge, which you can learn more about on our website.