Are Passive Houses Worth It? 5 Reasons We Say Yes

Passive Houses have become a major talking point for architects, designers and homeowners, particularly with energy efficiency at the centre of the recent updates to the National Construction Code (NCC).

Passive Houses harness building fabrics to create an energy-efficient envelope. Yet is it worth the investment in design and sustainable materials?

At Thermotek, we believe that Passive Design is a way of future-proofing a home against both the elements and market forces, particularly given the ongoing geopolitical volatility in the world and resulting unpredictability in costs. Plus, affordable Passive Design has become possible thanks to progress in manufacturing.

Let’s take a deeper look at Passive Houses and find out five reasons why it’s a design approach worth investing in.

Firstly, What Defines a Passive House?

The genesis of the Passive House is in Germany. The Passivhaus Institut was founded by Dr Wolfgang Fiest in 1991 and aims to create homes that are sustainable, ultra-low energy and comfortable, with outstanding ventilation and air quality.

It has become a globally influential design standard. The building envelope does most of the work to maintain an even, comfortable temperature without electrical input, thus lowering the carbon footprint.

The 5 Design Markers of a Passive House

Passive Houses take a “fabric first” approach, using a set of design principles to achieve energy efficiency rather than heating and cooling systems.

These are the design standards you’ll need to adhere to when building a Passive House:

1.     Airtightness

Passive Houses have an airtight building envelope. In effect, this means that there are very few gaps and cracks, reducing drafts and giving you total control over the internal air quality.

At Thermotek, our products are optimised to be airtight. Our window frames consist of various fusion welded air chambers. These give a superior seal which increases insulation, and the dual TPE (thermoplastic elastomer) seals further enhance thermal performance.

2.     Thermal Insulation

Excellent insulation provides a sufficient layer between the heated or cooled inside environment and the outdoors. This improves comfort and reduces condensation by minimising cold surfaces.

For example, the gap between the two panes in Thermotek windows is the main source of insulation, which slows down thermal transfer by conduction. The systems slow down air circulation to reduce the amount of heat lost in winter and gained in summer.

In winter, when cold air hits the first windowpane, it doesn’t reach the inside environment. Instead, it reaches the gas or air between the panes. By the time it hits the second pane, it is no longer freezing cold.

Thermotek systems keep your home’s temperature more stable, plus cuts down the number of times your heating/cooling system must switch on and off.

3.     Mechanical Ventilation Heat Recovery (MVHR)

The inclusion of a mechanical heat recovery system means you don’t need to open your windows for good air quality. This is a unit that effectively salvages heated and cooled air that would otherwise be wasted while also filtering the air that’s coming into the building. This means cleaner air plus a lower risk of condensation.

4.    The Removal of Thermal Bridges

‘Thermal Bridges’ are areas that cause increased heat consumption and increased condensation risk. The insulation needs to be a good thickness and continuous. This means keeping penetrations through the insulation to a minimum. If they must be made for construction, it should be done with materials that are less conductive, like timber. Or thermal breaks can be used, whereby a material that doesn’t conduct heat well separates two conductive materials (like metal).

5.     Passive House (High Performance) Windows

Windows should be double-glazed or triple-glazed, with thermally broken or non-metal frames. The size of the windows should also reflect the building envelope, to optimise solar radiation in summer and winter.

Now let’s take a look at why these design standards are worth incorporating into a residence…

Five Reasons Passive Houses Are Worth the Investment

1.     Passive Houses Lower Your Carbon Footprint

Passive Houses are incredibly sustainable thanks to the fact they require very little energy and emit little carbon, hence reducing greenhouse gases.

Passive Houses can help society meet emissions-reduction targets. In Australia, that’s reaching Net Zero by 2050.

2.     Passive Houses Lower Heating and Cooling Bills

Added to that, the clever design leads to low heating and cooling bills and excellent indoor air quality. Thanks to the airtight envelope and high-quality sealing, a Passive House is also very quiet to live in.
A passive house reduces energy costs by 70–80% because it is constructed with insulating materials and uses solar energy to generate heat. 

Therefore, you won’t need a fireplace, heaters, boilers, or other energy-intensive heating systems since the house will constantly be at the ideal temperature.

A solar panel installed on the roof will also drastically lower the energy cost. The house uses the sun’s heat to insulate itself from the cold throughout the winter. 

3.     They Offer Design Flexibility

Passive Houses are ‘fabric first’, meaning that certification depends on adhering to the design markers above, not the architectural style or scale of the home.

Previously, the style of Passive Houses was somewhat limited by the lack of fabrics on offer. Thanks to a surge in the popularity of sustainable design, manufacturers now offer more attractive designs. You also have many options when it comes to materials – whether that’s aluminium, wood, glass or something else.

4.     Living in a Passive House is Extremely Comfortable

According to the Australian Passive House Association, a Passive House ensures a long, durable building life, with light-filled spaces and high levels of comfort.

The air quality is also extremely good. All certified Passive Houses are Heat Recovery Ventilation-compliant (HRV-compliant). As a result, your home should maintain excellent air quality even if it’s locked up for months.

The HRV system constantly refreshes the air in the house without releasing the heat and has an air filter to purify incoming air.

5.     Passive Houses Require Little Maintenance

One of the great things about Passive Houses is that the focus on high-quality materials reduces the need for ongoing maintenance, saving money in the long run. For homeowners or strata organisations considering whether it’s a good investment, this is a major plus.

Getting the fabric of the building right from the start makes for longevity and sustainability and negates the need for retrofitting to achieve energy efficiency.

Passive Houses really are just that. There’s no need to turn the Mechanical Ventilation Systems on or off, although occasionally the filter may need to be replaced.

Thermotek Windows Help Achieve Passive Design

One of the important ways that Passive Houses achieve energy efficiency is through high-performance windows. At Thermotek, we believe that choosing the right window and door systems is key.

Thermotek windows are engineered in Germany and manufactured in Australia, crafted for outstanding thermal performance and energy efficiency.

The uPVC (unplasticised polyvinyl chloride) used has high thermal insulation properties, while the IGUs (insulated glass units) use standard Low-E glazing with argon gas.

Affordable Passive Design With Thermotek’s Eco Series 3000

A major concern that architects, builders and homeowners have about Passive Homes is the cost involved. Thanks to progression in engineering and local manufacturing, Thermotek are able to offer eco-friendly windows and door systems that are still affordable and enable Australian residential developments to meet energy ratings.

The Thermotek Eco Series 3000 windows and doors system is produced from the global German design and engineered 3-chamber Ideal 2000 uPVC profile by Aluplast. The streamlined 60mm profile is fully insulated with dual seals in the frame that caters for a wide range of opening configurations.

Crucially, it is more cost-effective than thermally broken aluminium, allowing architects and builders to achieve Passive Design and a genuinely high NatHERS energy rating without a gobsmacking bill.

Let’s Achieve Passive Design Together

Thermotek is an Australian market leader when it comes to passive design. We are also a low-waste manufacturer. All our products are 100% recyclable and manufactured in a sustainable way.

Contact our dedicated team today to find out more about using Thermotek window and door systems in a Passive House.