Help keep the Scottish Passivhaus equivalent on track

Overview	Passivhaus Trust response	Respond to the consultation
Share on social media	Contact your MSP	Glossary

• Read the Passivhaus Trust's detailed response to the Scottish Government’s consultation on its proposed Passivhaus equivalent policy. 

• Respond to the consultation to ensure the policy is ambitious and stays on track!

• DEADLINE FOR RESPONSES:  Wednesday 23 October 2024.

Overview

The Passivhaus Trust believes that, while there are some positive options towards a Scottish Passivhaus equivalent outlined in the consultation proposals, what is being proposed could fall significantly short of the intended aspirations.

 Jon Bootland, Chief Executive, Passivhaus Trust

The Passivhaus Trust welcomes the following elements within the consultation: 

• Deemed to satisfy: The Passivhaus Trust welcomes the inclusion of a proposal for certified Passivhaus homes to be considered ‘deemed to satisfy’ Scottish building standards within the consultation questions (Section 3.6);

• Quality assurance: The Trust welcomes the consultation’s exploration of quality assurance processes (Section 4).

• Timescales: We support the proposals for a stepped approach to bringing in the Scottish Passivhaus equivalent, with voluntary targets implemented in 2026 and mandatory targets from 2028. This transition period would allow for upskilling and training during a realistic timeframe once the industry has clarity on the exact policy requirements.

However, we are concerned that the proposals for modelling tools and targets are not sufficient to achieve a genuine Passivhaus equivalent:

• Accurate modelling tools: The consultation puts forward (Section 3.2) an as-yet undeveloped/ untested 'Scottish wrapper' for the Home Energy Model (HEM) software developed for the Future Home Standard (England). The Passivhaus Planning Package (PHPP) is a tried and tested modelling  and design tool that the Passivhaus Trust believes should be accepted as a modelling methodology until such time as the Scottish wrapper for HEM can be shown to produce energy forecasts with the same accuracy as PHPP.

• Absolute energy targets: The Passivhaus Trust strongly recommends the use of absolute targets based on heating demand, peak heating load and EUI (energy use intensity). It argues that the use of relative ‘notional building’ energy targets, as put forward in the consultation document (Section 3.3), will not deliver the performance required to achieve Passivhaus equivalent levels of comfort, indoor air quality and low energy bills.   

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Passivhaus Trust Response

Please click here to read our detailed response to the consultation.

If you are an organisation, please consider submitting a response to all 30 consultation questions, drawing on our detailed answers. Full responses will take a minimum of 1-2 hours. 

 

TAKE ACTION

 

1. Respond to the Consultation

You can use our key bullet points below to inform your responses to 9 key questions. It should take 10 minutes to respond. Our explainer video below goes through each question reponse in more detail. 

DEADLINE FOR RESPONSES:  Wednesday 23 October 2024.

Please put these into your own words and customise your answer to make it personal e.g. feel free to add your own comments on the importance of Scotland's climate leadership or draw on your experience of delivering Passivhaus buildings.  [Please note that identical and cut & pasted responses will not be counted.]

ANSWER: NO

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS]   Agree with points 1-2   Regarding Point 3:   Relaxing Passivhaus metrics risks performance gaps Passivhaus is prescriptive on absolute energy and comfort, not about specific building specifications. Passivhaus metrics are based on 30+ years of development and are proven effective through post-occupancy evaluations. Passivhaus metrics have been refined through transparent, evidence-based process

ANSWER: NO

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS]   Agree with points 1-3 and 6-12   Regarding Point 4, its essential that occupants can assess performance in use, so all methodologies must:  aim to match performance in-use  produce the same outcomes   Regarding Point 5, how can this be done if: the proposed standards are not being calculated using accurate methodologies? the standard does not include health and comfort metrics central to the Passivhaus Standard?   Regarding Point 10, in the context of ventilation solutions: the market should be free to develop suitable solutions for achieving indoor air quality (IAQ), heating metrics, comfort criteria, and fan power (where fans are used). the Passivhaus standard does not explicitly 'require' MVHR, but it does mandate that IAQ, heating metrics, and comfort criteria are met, this would discount some solutions.

ANSWER: NO

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] HEM with the 'Scottish Wrapper' is an unknown entity, as is yet to be developed. The English Wrapper for the Future Homes Standard review was disappointing. SAP, along with beta HEM and SBEM, produces outcomes that often fail to accurately reflect real-world performance. Passivhaus Planning Package (PHPP) offers a robust, accurate, and practical tool. PHPP supports both compliance and design, ensuring that buildings perform as intended. PHPP should be an approved methodology until such time as the Scottish wrapper for HEM is shown to produce energy forecasts with the same accuracy as PHPP.

ANSWER: NO

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] Only absolute targets can deliver a Scottish Passivhaus equivalent. Absolute targets ensure that all new buildings adhere to a specific performance level. Absolute targets are key recommendations from the Low Energy Transformation Initiative (LETI) in their Climate Emergency Design Guide. Absolute targets are promoted by the Royal Institute of British Architects (RIBA) in their climate work, and will be fundamental to the new UK Net Zero Carbon Building Standard (UKNZCBS).  Absolute targets ensure that all new buildings must meet the same high standard, making it easier to enforce and measure compliance. Absolute standards ensure that performance is consistently evaluated against a set criterion. The successful application of absolute targets in Scotland schools has set a model for achieving sustainability goals across all building sectors. Notional (relative) targets can lead to variability in performance expectations. Notional (relative) targets are based on comparisons and do not provide the clarity of absolute targets. Notional (relative) targets can penalise rather than encourage efficiency by design e.g. form factor and glazing ratios.

ANSWER: YES

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] A prescriptive space heating demand limit is crucial to drives higher standards of energy efficiency in new buildings. A prescriptive space heating demand limit, measured as heating demand (kWh/m²a) or a peak heat load (W/m²), maintains design flexibility. The Passivhaus standard demonstrates that setting these limits can result in buildings with exceptional energy performance.  Setting limits on space heating demand helps to minimise energy use, leading to lower utility bills for occupants and reduced carbon emissions. By reducing energy costs, absolute space heating targets can alleviate some of the financial burdens on vulnerable populations, helping to combat fuel poverty. Public health outcomes can also be improved by addressing issues related to cold and damp living conditions. Prescriptive limits can drive innovation and competition.

Consultation Question 7

Do you support the move to application of regional climate data within the approved calculation methodologies and their application within compliance targets? 

ANSWER: YES

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] Incorporate local climate data for accurate building performance. Tailor heating needs to specific regional climate conditions. Optimise summer comfort with regional cooling strategies. Ensure compliance targets reflect actual local climate conditions. Align heat load calculations with local climate data (important for heat pump sizing). Enhance building resilience to regional climate challenges.

Consultation Question 13

ANSWER: YES

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] Passivhaus Certification offers a feasible and effective alternative for compliance with Standard 6.1 (Energy Demand) and Section 3.14 (Ventilation).  The rigorous standards and comprehensive approach of the Passivhaus standard offer a reliable means of achieving high performance in energy efficiency and indoor air quality. Adopting Passivhaus Certification as an alternative means of compliance would support Scotland in scaling up and enhance industry readiness for a Scottish Passivhaus equivalent.

Consultation Question 30

Do you agree with the proposal to mandate the standard in 2028, introducing changes initially as a voluntary standard from 2026?

ANSWER: YES

[PLEASE SELECT SOME OF THE FOLLOWING & PUT THEM INTO YOUR OWN WORDS] The Scottish Passivhaus equivalent standard should be implemented through a phased approach, becoming voluntary in 2026 and mandatory from 2028.  A phased transition provides the industry with adequate time to upskill and train ready for the mandatory standard.  Implementing the standard initially on a voluntary basis will offer valuable insights and allow industry stakeholders to adapt. A phased transition would accelerate the adoption of higher standards. It is essential that the initial voluntary period is used to support industry transformation.

Join our LAST CHANCE lunchtime webinar on Tuesday 22 October, offering set-by-step support for consultation responses.

 

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2. Share on social media

Please let us know you have responded, share the Passivhaus Trust's key messages and encourage others to respond!

• Share our LinkedIN Post
• Share our X Post
• Tag the Passivhaus Trust in any posts
• Use the hashtag: #ScottishPassivhausEquivalent
• Please drive traffic towards: https://bit.ly/PHTScottishPassivhausEquivalent

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3. Contact your MSP

Please email your MSP to ask them to support the Passivhaus Trust’s position on the Scottish Passivhaus equivalent consultation. Use the suggested email text below to get in touch and let us know if you hear back from them.

a)       Find your MSP

If you live in Scotland, please enter your postcode or location to find the email address of your local MSP. https://www.parliament.scot/msps/current-and-previous-msps

b)       Email using suggested text

Dear [Name of MSP]

As one of your constituents,  I wanted to share my concerns about some of the current Scottish Government consultation proposals for the Scottish Passivhaus equivalent policy. I would like to ask you would get behind amendments to the consultation proposals suggested by the Passivhaus Trust.

Introducing a Passivhaus equivalent would put Scotland on a global stage for climate leadership, help alleviate fuel poverty, and improve energy security in Scotland. However, there are concerns that many of the current proposals set out in the consultation do not fully align with these aspirations, and if adopted, would fall significantly short of achieving meaningful impact. The good news is that the consultation references all the essential elements needed to set Scotland on the right track toward a genuine Passivhaus equivalent.

The Passivhaus Trust is very supportive of the inclusion of a proposal for certified Passivhaus homes to be considered ‘deemed to satisfy’ Scottish building standards and the consultation’s exploration of quality assurance processes. It also supports the proposals for a stepped approach to bringing in the Scottish Passivhaus equivalent, with voluntary targets implemented in 2026 and mandatory targets from 2028. However, the Passivhaus Trust is concerned that the proposals for modelling tools and metrics are not sufficient to achieve a genuine Passivhaus equivalent:

You can read and watch a video giving an overview of the Passivhaus Trust’s position on the consultation proposals here:

https://www.passivhaustrust.org.uk/news/detail/?nId=1352

It would be fantastic if you could respond to the Consultation, making the points that the Passivhaus Trust has identified, to help keep the Scottish Passivhaus Equivalent policy on track.

I look forward to hearing from you.

Best wishes

[Name]

[Address]

 

c)       Send us any MSP responses

Please forward any MSP responses you receive to info@passivhaustrust.org.uk

It will be helpful for the Passivhaus Trust to know which MSPs are supportive of the Scottish Passivhaus equivalent policy, which will be useful at later stages as the legislation comes to the Scottish Parliament. 

 

 

Glossary

Relative vs Absolute targets

The simplest way to explain the difference between relative and absolute targets is to compare it with the metrics used to buy a car. Consumers would expect to be able to compare car fuel efficiency based on the ‘absolute’ metric of miles per gallon. In contrast, using a relative 'notional' metric would be like comparing cars based on a percentage improvement relative to an undefined, hypothetical car. This method not only makes it difficult to make informed purchasing decisions, but also complicates understanding as to whether a new car meets its design targets once in use. 

 

Relative ‘notional building’ energy targets

The relative ‘notional building’ method involves comparing the proposed building with a reference building, known as the ‘notional building,’ which is built to meet certain predefined energy performance standards. This method does not necessarily drive energy reductions for the following reasons:

1. Relative comparison:

• The notional building sets a benchmark for energy performance based on current standards, but it does not necessarily incentivise improvement beyond this benchmark. Developers are only required to match or slightly exceed the performance of this notional building, leading to a "minimum compliance" mindset.

2. Fixed standards:

• The standards for the notional building may become outdated over time. If the baseline standards are not regularly updated to reflect advances in technology and best practices, the method fails to push the envelope for greater energy efficiency.

3. Trade-offs:

• The method allows for flexibility in how compliance is achieved e.g. you can choose to compensate for poorer performance in one aspect of the building design (like insulation) with better performance in another (like efficient HVAC systems). The focus becomes one of balancing trade-offs rather than achieving the lowest possible energy use.

4. Focus on compliance rather than performance:  

• Because the goal is to match the notional building, the focus is on compliance with the regulations rather than on optimising the building’s overall energy performance. The less efficient your building, the easier it is to achieve (relative) compliance, whilst your building consumes more energy that it could or should.

Absolute energy targets

Absolute energy targets, on the other hand, set a specific maximum level of energy consumption that a building must not exceed, regardless of how this is achieved. This approach is more effective in driving energy reductions for the following reasons:

1. Clear and fixed goals:

• Absolute energy targets provide a clear and unchanging goal for energy consumption. This sets a definitive benchmark that must be met or exceeded, encouraging more innovative and effective approaches to energy efficiency.

2. Performance-based:

• The focus is on the actual energy performance of the building, rather than on relative performance compared to a notional standard. This drives designers and builders to seek out the best possible solutions for reducing energy use, leading to real and measurable reductions in energy consumption.

3. Encouragement of best practices:

• Because the targets are absolute, there is a strong incentive to adopt the latest technologies and best practices in building design and construction. This can include better insulation, more efficient HVAC systems, and renewable energy integration.

4. Future-proofing:

• Absolute targets can be set with future standards in mind, encouraging buildings to be designed to higher efficiency standards that anticipate future regulatory requirements. This can lead to longer-term energy savings and a reduction in the building’s overall environmental impact.

Regulated & unregulated energy

Regulated energy

Regulated energy is building energy consumption resulting from fixed building services such as space heating,  hot water, ventilation,  and lighting.

Unregulated energy

Energy Use Intensity (EUI)

The absolute Energy Use Intensity (EUI) metric includes both regulated and unregulated energy. The EUI metric  is vital for effectively monitoring and driving performance. EUI provides a clear, absolute target that corresponds with actual meter readings, thereby empowering end users with comparable data and helping to close the performance gap.

The Passivhaus Trust argues that absolute EUI  targets for total energy usage, including both regulated and unregulated energy, are crucial to drive meaningful change and achieve genuine reductions in energy consumption

 

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Thanks to our campaign sponsors

The Passivhaus Trust's Scottish Passivhaus equivalent policy work is kindly campaign is sponsored by the following Passivhaus Trust members:

If you would like to become a campaign sponsor, please email info@passivhaustrust.org.uk

Further information

Building regulations - energy and environmental standards: consultation on proposed changes

Scottish Passivhaus Equivalent: FAQs

Passivhaus for Scotland showcase

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14th September 2024

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