How To Get A Comfortable, Healthy, Energy Efficient Home Without Condensation, Mould, And Air Quality Issues
Airtight homes naturally maintain a stable, comfortable temperature all year round (between 18-22 degrees) without being dramatically affected by external weather. Any extra heating and cooling that might be needed, will be minimal, thus saving you energy. Sounds like a dream come true, right? A home that stays cool in summer and warm in winter with minimal air-conditioning. But there are some potential downsides.Condensation and Mould
The lack of air circulation and significant temperature differential between inside and outside the home can cause condensation that may lead to moisture and mould issues. General living – boiling the kettle, taking a shower, and even breathing — creates heat and moisture. When this warm, moist air comes into contact with internal walls that are ‘bridged’ to cooler external walls, it can condense to form moisture. If left to sit, this moisture can provide an environment that encourages mould to grow.Increased CO2
An airtight home can also lead to increased CO2 levels which can cause the occupants to feel tired and lethargic. We’ve all experienced this when gathering for meetings in a small room. As CO2 levels rise, everyone starts to yawn.Internal Air Quality
And an airtight home can also promote the accumulation of odours and excess toxins in the air from cooking (especially from gas appliances). What’s the solution? How can you have a comfortable, healthy, energy efficient home without condensation, mould, and air quality issues? Firstly, you must minimise thermal bridges in your home. That is, eliminate points where the external temperature can conduct through building materials into the internal surfaces of your home. The right insulation (installed with attention to detail) is critical. So too is minimising the use of conductive materials (e.g. use uPVC window frames rather than aluminium). Secondly, you must ventilate your home. And you have to do this in a way that doesn’t compromise the internal temperature. This is achieved through a Mechanical Heat Recovery Ventilation System. This clever system draws air from outside your home, heating it via exchange with the internal air before releasing it into your home. It refreshes the air in your home without making it cold. If you want a home that is energy efficient and comfortable all year round it must be airtight. But airtight(ness) is just one of the five principles to building a truly energy efficient home. For more information about how to use all five principles of energy efficient building, we invite you to where we will answer your questions and show you the most efficient and affordable ways to get a healthy, comfortable custom home you’ll love forever.Frequently Asked Questions
What are the downsides of an airtight home?
Without the right detailing, an airtight home can suffer condensation and mould, raised CO2 levels that leave occupants tired and lethargic, and a build-up of odours and cooking toxins, especially from gas appliances. Each of these is solvable with the right design.
Why do airtight homes get condensation and mould?
Everyday living such as boiling the kettle, showering and even breathing creates warm, moist air. When that air meets internal walls that are thermally bridged to cooler external walls, it condenses into moisture, and moisture left to sit creates the environment mould needs to grow.
How do you prevent condensation and mould in an airtight home?
First, minimise thermal bridges, the points where external temperature conducts through building materials to internal surfaces. The right insulation installed with attention to detail is critical, as is reducing conductive materials, for example using uPVC window frames rather than aluminium.
How does an airtight home stay healthy and fresh?
Through a Mechanical Heat Recovery Ventilation system. It draws air from outside, warms it by exchange with the internal air, then releases it inside, refreshing the air without making the home cold and keeping CO2, odours and toxins under control.
Is an airtight home still worth building?
Yes. An airtight home naturally holds a stable, comfortable temperature of 18 to 22 degrees all year round with minimal heating and cooling. Airtightness is one of the five principles of a truly energy-efficient home, and done properly with ventilation, the downsides are designed out.
