Understanding the 5 principles of Passivhaus design

Last year, it was reported that an estimated 10 million homes in the UK were leaking air and poorly insulated, resulting in an adverse domino effect for homeowners. From energy loss to the consequential increase in energy bills and overall occupant discomfort, airtight construction is crucial for new builds. It removes the repercussions of air loss and instead fosters a cost-effective and cosy indoor environment.

Airtight construction prevents uncontrolled leaks or gaps – a process which again derives from the initial design phase. Drawing on our expertise as Architects and designers, it’s our obligation to finalise plans that’ll guide the sealing of low-energy, high-performance, beautiful buildings.

With a trusted pre-insulated panel system in your peripheral, we’d then recommend exploring passive foundation solutions, such as those offered by ISOQUICK® (expanded in point 4), before turning to precision air sealing technologies. AeroSealUK, for example, is the industry’s only plug-and-play air sealing system, which eliminates leakages and reduces energy usage by 40%.

Last but by no means least in terms of airtight construction, an energy-efficient design will not be awarded Passivhaus certification without the careful selection of pre-installed joinery:

Buildings commonly lose heat through windows and doors. Therefore, it’s essential to pay close attention to the specification of joinery for new projects. This will not only help minimise heat loss but also maximise the potential of the other high-performance products and technologies working collectively, as mentioned above.

Essential criteria to look out for when choosing joinery include:

• A Passive House Institute stamp of approval.
• CE marking.
• Triple-glazed windows with insulative frames.
• Low U-values (low U-values indicate high levels of insulation and, in turn, low heat loss).

As there’s a strong correlation between a building’s performance and its architectural design, factors such as orientation, glazing-to-frame ratio, and the number of windows incorporated will also impact both solar gain and the efficiency of a Passivhaus project.

Here at Elements By Oakwrights, we proudly partner with Rationel, who produce award-winning, sustainable, triple-glazed joinery that’s versatile, durable, modern in aesthetics and can be installed within our panel systems prior to being delivered to site.

Also known as cold bridges, thermal bridges are weak spots within a building’s envelope where heat can easily transfer.

Typically occurring when materials enter an insulative layer, as well as at corners or joints, it’s suggested that thermal bridging alone can be responsible for up to 30% of a building’s heat loss, closely followed by the connected ramifications.

So, where do we begin to counteract these causes?

A significant step in our creative journey with clients is to take a meticulous approach when selecting innovative building materials, products, and technologies, starting from the ground up. At the core of our offering here at Elements by Oakwrights is ISOQUICK’s insulated foundation system, a proven solution for minimising thermal bridging and delivering consistent, robust energy performance.

Thermal bridges reiterate the importance of integrating these five Passivhaus principles into our contemporary architectural designs. A preventive, holistic strategy holds the key to achieving uniform and super-insulative envelopes.

A defining technology found within the hub of a Passivhaus is an MVHR system.

Their role is invaluable yet straightforward in energy-efficient designs and builds: to extract stale air from rooms and replace it with an equal amount of fresh, filtered air while retaining heat. 

To guarantee your clients’ high-performance, healthy homes, it’s vital to strike the perfect balance between interior ventilation and airtightness. Click here to view the Passive House Institute’s visual representation of an MVHR system at work.