The UK‘s approach to building performance is changing. As new standards reshape how we measure energy efficiency, heating, ventilation and occupant wellbeing, what does this mean for projects being designed today?  

The countdown to 2030 is already underway. Over the next five years, a series of regulatory changes will reshape how buildings across the UK are designed, assessed and operated. From the introduction of a new multi-metric approach to Energy Performance Certificates (EPCs) and the Future Homes Standard, to growing requirements around indoor air quality and occupant wellbeing, the focus is shifting beyond simply meeting minimum energy efficiency requirements.  

For developers, architects, engineers, and building owners, this means decisions made today could have a significant impact on a building’s ability to meet tomorrow’s standards. The challenge is no longer simply how to achieve compliance, but how to deliver buildings that demonstrate better long-term performance.  

So, what exactly is changing? 

The road to 2030 isn’t defined by a single piece of legislation. Instead, the built environment is facing a period of significant regulatory change, with updates to building regulations, energy performance assessments, and minimum efficiency standards all expected over the coming years. 

Among the changes published updates to Parts L and F of the Building Regulations, potential revisions to Part O, the planned transition from SAP to the Home Energy Model (HEM), and changes to the Minimum Energy Efficiency Standards (MEES). 

“The scale of change makes it difficult to identify a single defining development. However, the proposed tightening of Minimum Energy Efficiency Standards for privately rented properties could have the most significant and widespread impact. The direction of travel is clear.” Steven Carroll, Senior Sustainability Consultant, shared with us.

Rethinking the EPC

One of the most visible changes will be the reform of EPCs. In England and Wales, the proposed introduction of the Home Energy Model will replace the current SAP methodology for domestic assessments, alongside a new multi-metric approach to EPCs.  

Rather than reducing building performance to a single energy efficiency rating, the proposed EPC framework provides a more nuanced assessment by separately reporting fabric performance, heating system efficiency, smart readiness, and energy cost.  This could provide developers, building owners, and project teams with a more balanced picture of where a building performs well and where improvements may be needed.  

“The proposed multi-metric EPC framework should provide a more balanced assessment of building performance,considering fabric efficiency, energy costs and heating-system performance separately, while helping to highlight potential trade-offs that can exist between operational costs and decarbonisation objectives.” Steven shared. 

However, it’s important to distinguish between improved modelling and actual building performance. As Steven notes, EPCs will remain modelled assessments rather than measurements of how a building performs in use. 

“EPCs will remain modelled assessments rather than measures of actual building performance,” he explained. 

The transition will not look identical across the UK, either. While England and Wales are proposing a shift towards an Energy Cost Metric based on annual fuel costs, the Scottish Government has indicated an intention to retain an A–G style rating alongside its equivalent energy cost metric. So, for organisations working across multiple UK markets, understanding these differences will be important when planning projects and assessing future compliance. 

A fabric-first approach

The changes to EPCs are only one part of the picture. Meeting future performance standards will also require project teams to think differently about how buildings are designed from the outset. 

A fabric-first approach — reducing energy demand through measures such as improved insulation, airtightness and thermal-bridge mitigation — will remain fundamental. But as buildings become more efficient, simply adding further fabric improvements can deliver diminishing returns. 

“There are diminishing returns from fabric enhancements. Beyond a certain point, further improvement can become increasingly cost-ineffective.” shared Steven.

This makes the relationship between the building fabric and its services increasingly important. Rather than treating them as separate considerations, projects need to balance fabric performance with ventilation, heating, thermal comfort, and efficient operation. 

The challenge for project teams is to find the right balance between reducing energy demand and designing building services that can operate efficiently, maintain comfortable internal conditions and support good indoor air quality. 

This means MEP considerations need to be brought into the conversation early — rather than being treated as a solution to be added once the building fabric has already been defined. 

Designing for low-carbon heating and effective ventilation

A fabric-first approach can reduce a building’s energy demand, but it is only part of the picture. As buildings become more airtight and heating systems move away from fossil fuels, the relationship between building fabric, heating and ventilation becomes increasingly important. 

Heat pumps are expected to play a much greater role in meeting future heating requirements, making it increasingly important to minimise heat demand through effective insulation, airtightness, and thermal-bridge mitigation. At the same time, well-designed ventilation is essential to maintain good indoor air quality, manage moisture, and provide comfortable internal conditions. 

Steven also shared that “as heat pumps become the norm, reducing heat demand becomes increasingly important.” 

This is where the principle of “build tight, ventilate right” comes into play. Improving airtightness can reduce unwanted heat loss, but it needs to be supported by an effective ventilation strategy. For project teams, this reinforces the importance of considering fabric and MEP design together from the outset, rather than treating building services as a separate consideration. 

Building performance and occupant wellbeing 

Alongside energy performance, increasing emphasis is being placed on the health and wellbeing of building occupants. Issues such as damp, mould, overheating and indoor air quality are becoming increasingly prominent within policy, regulation and industry guidance.  

The introduction of Awaab’s Law, together with a growing focus on healthy indoor environments, reinforces the importance of designing buildings that not only operate efficiently but also provide safe, comfortable and resilient places to live and work. As buildings become increasingly airtight and energy efficient, achieving appropriate levels of ventilation, moisture control and thermal comfort will be essential to balancing building performance with occupant wellbeing. 

What should projects do now? 

With many of these changes still developing, project teams do not need to wait for every detail to be finalised before taking action. The direction of travel is clear: buildings will need to be more energy efficient, better prepared for low-carbon heating and capable of delivering good performance in practice. 

For projects being designed today, this means looking beyond current minimum standards and considering enhanced fabric performance, airtightness, overheating mitigation, robust ventilation, heat pump or heat network readiness, and viable opportunities for solar PV from the outset. 

 “The objective should be to deliver buildings that are resilient, cost-effective and future proof, rather than simply compliant with current requirements.” 

The key milestones below highlight the pace of change and the deadlines project teams should have on their radar as we move towards 2030 and beyond.

Preparing for these changes is ultimately about more than meeting the next regulatory requirement. By considering building performance holistically and making informed decisions early, project teams can create buildings that are better equipped to respond to changing regulations, energy costs and occupant needs over their lifetime.  

The regulatory landscape is changing quickly, and understanding what these changes mean for individual projects will be key to making informed decisions today. 

We can help you navigate the evolving requirements, identify opportunities to improve building performance and develop strategies that are designed to go beyond compliance. 

Get in touch with our Sustainability team to discuss how we can help prepare your project for 2030 –  [email protected]

With temperatures reaching 38.1°C in parts of the UK and London facing a rare risk-to-life heat alert, the country’s fifth heatwave of the year is putting building performance firmly back in focus.

For decades, the focus has rightly been on reducing heat loss, improving insulation, and lowering winter energy demand. Those priorities remain critical. But as hotter summers become more common and unpredictable, another challenge is becoming increasingly important: overheating.

This summer’s heatwaves are a reminder that many of the UK’s commercial buildings were designed for a different climate, whereas now we are faced with less predictable weather, and more frequent extremes.

When temperatures rise, it’s common to hear concerns about well-insulated buildings becoming “thermal traps”. In reality, overheating is rarely caused by insulation alone.

More often, it is the result of an imbalance in the overall design, where heat is allowed to enter the building or build up internally without an effective strategy to control or remove it.

High-performing building fabric remains a fundamental part of good building design. It helps reduce energy demand, improve comfort and stabilise internal temperatures throughout the year. The challenge comes when solar gains, internal heat loads, ventilation strategies, controls and cooling systems are not considered together as part of a holistic approach.

In many offices, overheating is driven by a combination of factors, including large areas of unshaded glazing, poor solar control, limited ventilation, significant internal heat gains from people and equipment, and building designs based on historic weather data rather than future climate projections.

The result can be uncomfortable working environments, reduced productivity and increasing cooling demands.

When temperatures rise, the immediate question is often whether a building needs more cooling. The best-performing buildings start by reducing overheating risk through good design.

This shift is already being reflected in planning policy. The Greater London Plan, for example, encourages designers to address overheating through a cooling hierarchy, prioritising measures such as orientation, shading and ventilation before relying on active cooling. It reflects a broader change in thinking across the industry: designing buildings that stay comfortable through good passive design first, with active cooling used only where necessary.

That means understanding the full thermal balance of a building. How much heat is entering through the façade? How effectively can excess heat be removed? How will the building perform not only today, but throughout the hotter summers expected over its lifespan?

When assessing future building performance, at Wallace Whittle we consider factors such as solar gain, ventilation strategy, building fabric, future climate modelling and, where necessary, the most efficient and sustainable approach to active cooling.

The most resilient buildings are not necessarily those with the largest air-conditioning systems. They are the ones where thermal comfort has been considered from the outset, creating buildings that retain heat when it is needed, keep unwanted heat out when temperatures rise, and remove excess heat efficiently when it builds up.

As periods of extreme summer temperatures become more common across the UK, designing for overheating is no longer a secondary consideration. It is becoming a fundamental part of delivering comfortable, healthy and energy-efficient buildings for the future.

Designing for a changing climate requires a balanced approach to building performance.

If you’re looking to better understand overheating risk, future climate resilience or cooling strategies for an existing building or new development, get in touch with our Sustainability team at [email protected]

The landscape of hospital delivery is shifting rapidly. No longer can critical considerations like clinical risk, digital integration, and sustainability be treated as “add-ons” to be addressed at the end of a design; today, they must shape the brief from day one.  

At Wallace Whittle, our UK-wide healthcare experience has shown us that HTM-led assurance has become the essential foundation for navigating these complexities. By treating Health Technical Memoranda (HTMs) as the living “backbone” of the engineering process rather than a mere administrative checklist, we ensure that safety, operational resilience, and net zero ambitions are woven into the very fabric of modern clinical environments.  

HTMs The backbone of how healthcare buildings are engineered  

Health Technical Memoranda (HTMs) form the foundation of how healthcare environments are designed, delivered and operated across the UK. Developed by NHS England, they represent the most comprehensive set of engineering guidance in the sector, setting out not just what systems are required, but how they should perform, integrate and be maintained over time. 

They span every critical aspect of a hospital’s infrastructure, from ventilation and infection control to water safety, medical gases, electrical resilience, and fire strategy. Importantly, HTMs go beyond technical compliance. They embed clinical risk management into engineering design, ensuring that building systems actively support patient safety, staff wellbeing, and operational continuity. 

At the same time, HTMs work in parallel with NHS England, aligning engineering performance with how clinical spaces are planned and used. This relationship is key. It ensures that infrastructure and environment are not designed in isolation, but as part of a coordinated, functional healthcare setting. 

We treat HTMs as a living part of the design process rather than a static set of rules. Instead of applying them as a final compliance check, we bring them into projects from the earliest stages. This allows them to inform key decisions around system selection, spatial coordination, resilience strategies, and long-term maintenance. 

By embedding HTMs early, we are able to identify risks sooner, reduce redesign later in the programme and create a clearer path through approvals and validation. It also ensures that by the time a project reaches commissioning, compliance is not something to be proven; it is something that has already been designed. 

Why standardisation matters 

HTMs work alongside the Health Building Notes programme to create a consistent framework for how clinical spaces are planned, engineered and operated. They ensure that while hospitals may differ in size, shape and function, the underlying systems that support patient care behave in a predictable, safe and repeatable way. 

This consistency is critical in healthcare environments where reliability is non-negotiable. Standardisation reduces ambiguity in design decisions, aligns expectations across multidisciplinary teams, and helps ensure that engineering solutions are tested against recognised benchmarks from the outset of a project. 

In practice, we see the benefits of this approach across every stage of delivery: 

• Designs progress more smoothly with fewer late-stage changes  

• Coordination between disciplines is more efficient and transparent  

• Commissioning and validation are more structured and predictable  

• Clinical teams experience familiar, dependable environments that support safe operation  

Standardisation does not mean uniformity. It does not produce identical hospitals. Instead, it ensures that the most critical systems, the ones that directly impact safety, infection control and operational resilience, function in a way that clinicians can trust, regardless of location or project scale.

System-specific assurance where safety is embedded 

Each HTM focuses on a specific aspect of healthcare infrastructure, providing detailed guidance that connects engineering performance directly to patient safety and clinical outcomes. 

Key examples include: 

• HTM 03-01 – ventilation and healthcare-associated infection control  

• HTM 04-01 – water systems, including Legionella risk management  

• HTM 02-01 – medical gas pipeline systems and critical life support infrastructure  

• HTM 05 series – fire safety strategy and evacuation resilience in healthcare settings  

• HTM 06-01 – electrical services supply and distribution 

Rather than treating these as standalone documents, we integrate them into every stage of design development. They are embedded within technical reviews, coordination workshops, commissioning strategies, and validation processes. This ensures that compliance is not only achieved but fully understood and demonstrated at every stage of delivery. 

Example in practice  

A strong example of this approach can be seen in our recent work on Victoria Infirmary, where early-stage HTM alignment significantly influenced both system design and delivery sequencing. 

By applying HTM requirements at the concept stage, particularly around ventilation performance (HTM 03-01), HTM 06-01 electrical services and water safety (HTM 04-01), key engineering decisions were resolved before detailed design began. This reduced late-stage redesign, improved coordination between mechanical and electrical systems, and streamlined the commissioning process.  

Crucially, it also gave the clinical team confidence that critical safety systems had been considered from the outset, not retrospectively validated at handover. 

This early alignment meant that when the project reached commissioning, the focus shifted from resolving compliance issues to verifying performance, accelerating practical completion, and improving overall delivery confidence. 

Net zero and sustainable design within an HTM framework 

As healthcare design evolves, HTMs are no longer viewed solely through the lens of safety and compliance. They are increasingly shaping how hospitals respond to wider national priorities, particularly the drive towards net-zero carbon within the NHS. 

Rather than sitting alongside sustainability targets, HTM requirements directly influence the parameters within which low-carbon design must operate. Factors such as ventilation performance, energy efficiency, thermal comfort, and system resilience must all be achieved without compromising the clinical safety standards set out in HTM guidance. 

This creates a clear design challenge: delivering high-performing, low-carbon buildings while maintaining strict technical and operational requirements. It is within this balance that the role of engineering becomes critical. 

Our approach is to integrate sustainability modelling and carbon reduction strategies from the earliest stages of design, ensuring they are developed in parallel with HTM compliance rather than introduced afterwards. This allows net-zero ambitions to be embedded in system selection, plant strategies, and spatial planning from the outset, rather than retrofitted later in the process.

Delivering this balance requires more than technical compliance. It depends on a deep understanding of how healthcare environments function in practice, and how engineering decisions directly affect clinical outcomes. 

Across our UK offices, our healthcare engineers bring that understanding to a wide range of environments, including community healthcare settings, elective care facilities, acute hospitals, mental health units and complex surgical environments. 

This breadth of experience informs how we approach every project, with a focus on quality, resilience and long-term performance, as well as the practical realities of how spaces are used day to day.  

As the New Hospital Programme moves forward, HTM-led assurance will be central to delivering hospitals that are safe, sustainable and built for the future. 

We’re keen to connect with others shaping this next phase of healthcare delivery. Reach out to our Healthcare Team today at  [email protected]

The incoming Future Homes Standard is anticipated to fundamentally change how residential schemes are designed, costed and delivered, going beyond the requirements of the current Building Regulations. 

From 2025, new homes are expected to produce around 75–80% fewer carbon emissions than homes built to the 2013 Part L Building Regulations baseline, largely attributed to utilising low-carbon heating as a default, an improvement in building fabric energy efficiency, and a new, more complex energy modelling methodology through the introduction of the Home Energy Model (HEM).

For developers and project teams, the Home Energy Model ensures that the assessment of building energy performance is no longer just a compliance exercise, as it will now require and consider a more in-depth look into:  

• Heating strategies and plant space  

• Electrical infrastructure and grid capacity  

• Design coordination between architecture and MEP  

• Programme sequencing and early-stage decision-making  

• Capital cost and long-term asset performance  

The direction of travel is clear, but the question is: Is your current project pipeline aligned with it.  

Projects that treat the Future Homes Standard as a late-stage regulatory hurdle increase the risk of redesign, delay , and avoidable cost uplift. Those clients and developers seeking to incorporate the requirements early in the design can plan for greater compliance margins, an increase in project viability, and improved energy performance from the outset.  

What is the Future Homes Standard?

The Future Homes Standard (FHS) is a set of mandatory regulations designed to significantly reduce carbon emissions from new homes in England. Its primary goal is ambitious, but by 2025, all new homes should emit 75–80% less carbon, and equivalent emissions than homes built under the current regulations. The standard represents a major step in the UK’s journey toward net-zero housing, supporting the decarbonisation of domestic energy use by utilising the rapidly increasing number of renewable energy systems coming online to the UK national electricity grid.  

The FHS is part of a broader strategy to tackle climate change while maintaining practicality and affordability for developers and homeowners. It does this by mandating high-performance building fabric energy efficiency, installation of low-carbon heating systems, and increasing the requirement for provision of renewable energy. Unlike previous updates to Building Regulations, the FHS also introduces a new approach to compliance and modelling through the Home Energy Model (HEM), which allows for more detailed, dynamic, and realistic assessments of a building’s energy performance.  

While the goals are clear, the rollout of FHS has not been without challenges. The programme has experienced delays with arrangements still being finalised, including ongoing questions around training, accreditation, and the impact on project costs and timelines.  

What are the key changes?   

For developers, designers, and consultants, the key changes go beyond compliance and will influence decisions much earlier in the project lifecycle. 

Modelling, Skills, and Workload  

One of the most significant changes introduced by the Future Homes Standard is the transition away from the Standard Assessment Procedure (SAP) as the primary compliance tool. In its place, the Home Energy Model (HEM) will provide a more detailed approach to assessing energy performance.  

While both tools aim to demonstrate regulatory compliance, the methodology, level of detail, and practical implications for design teams differ quite considerably. The table below outlines the key distinctions between SAP and HEM, and what they mean in practice.  

Market Impact & Opportunities  

As the industry prepares for the transition, many organisations are already reviewing design strategies, heating specifications and development programmes to understand how the Future Homes Standard may affect current and upcoming schemes. Craig Robertson, our Director for England shared with us: 

“The Future Homes Standard brings a much-needed sense of direction and alignment across the residential sector in England. While the initial cost implications can feel daunting, many developers are already embracing the shift and recognising the long-term benefits of improved building performance and electrification. 

At Wallace Whittle, we are fully engaging with initiatives such as the Future Homes Hub to stay ahead of the transition. Early decisions at client brief stage, particularly around heating strategy and energy performance, are now critical to managing cost and programme risk. 

We also hope to see continued alignment between the Future Homes Standard and Section 6 requirements in Scotland, helping to create greater consistency across the UK market.” 

Challenges, Uncertainty and the Journey Ahead 

However, delays to publication, uncertainty around transitional arrangements, and concerns over software readiness have created some hesitation across the industry.  

Developers may face a slight increase in upfront capital costs, tighter design coordination, and longer modelling processes. Design teams must commit to key decisions earlier in the project lifecycle, while assessors and local authorities prepare for higher workloads.  

There are also broader questions surrounding affordability, viability, and embodied carbon regulation, which remains outside the scope of national Building Regulations for now. For some, it feels ambitious; for others, it is long overdue.  

While some elements of the FHS are still to be  finalised, the direction is sufficiently clear to begin meaningful early-stage assessments. With SAP 10.3  expected to be released alongside the FHS, and HEM to follow shortly after, there will be a defined transition period being SAP is fully retired, likely no earlier than Summer 2029.   

What Developers Should Be Thinking About Now

The transition to the Future Homes Standard will require changes across the entire residential delivery process, from early design decisions through to construction and compliance assessment. 

For developers and housing providers, one of the most important steps is ensuring design teams are prepared for the shift in how domestic energy performance will be modelled and assessed. The introduction of the Home Energy Model represents a significant change from the established SAP methodology, and the industry will need time to develop the necessary skills and processes. 

Skills gaps and design team readiness are already emerging as potential challenges. Responding to regulatory change is never straightforward, and with the Future Homes Standard introducing new modelling approaches and performance expectations, many project teams will need to adapt their design strategies and technical understanding. 

At the same time, uncertainty around final regulatory details and implementation timelines presents a further risk for developers progressing schemes in the near term. Clients may be working to specifications and cost assumptions based on current regulations, which may not fully align with the final Future Homes Standard requirements. 

Early engagement and informed decision-making will therefore be critical. Considering energy strategy, heating systems and building performance at the earliest stages of project development can help reduce the risk of late design changes or additional costs as the new standards are implemented. 

Wallace Whittle works with developers, housing providers and contractors to help navigate the transition to new regulations and standards. 

Our sustainability specialists are actively engaged in residential low-carbon design and assessment, working closely with accreditation partners and industry bodies to monitor developments around the Future Homes Standard. This allows us to provide clients with early insight into likely requirements and the potential impact on design, specification and programme. 

Through early-stage energy strategy, compliance modelling and heating strategy optioneering, we help clients understand both the risks and opportunities associated with the transition. Our focus is on ensuring that development plans remain viable, while aligning projects with the evolving regulatory landscape. 

With a long track record in the residential sector and strong industry partnerships, we are well positioned to support developers in managing this transition and preparing schemes for the Future Homes Standard. 

Our specialists are supporting clients in navigating the transition to low-carbon compliance. From early-stage feasibility through to detailed modelling and delivery, we can help ensure your project is ready for what’s ahead. Get it touch with our team at [email protected]