Roasting residents. Soaring complaints. Uninhabitable conditions.

If your building is reaching 40–45°C indoors during summer, it’s not just the weather – it’s a maintenance warning sign. And it’s affecting your residents’ health, your energy bills, and your reputation.

As temperatures rise, overheating in residential buildings continues to be a growing concern. While many assume it’s simply the result of hot weather and solar gain, the reality is often far more complex.

The Hidden Causes of Overheating in Modern Buildings.

Overheating is often assumed to be caused by solar gain – but that’s rarely the full story. In most cases, the building’s own systems are silently turning up the heat.

Here’s what might be going wrong:

• BMS not seasonally adjusted – The building still thinks it’s winter and continues pumping heat.
• HIUs (Heat Interface Units) not serviced – Faulty or inefficient units contribute to temperature imbalances.
• No pump cycle control – Constant heat circulation, even when it’s not needed.
• Poor insulation (lagging) – Heat escapes from pipework into risers and communal areas.
• No shut-off strategy – Communal heating running year-round, even in 30°C weather.

These are all fixable – but left unresolved, they create spiralling energy costs, frustrated residents, and unnecessary wear on your system.

“One of the biggest misconceptions I come across is that overheating is simply a consequence of warm weather. While external temperatures certainly play a role, they don’t always explain why some buildings become significantly hotter than others.

 

When we investigate overheating issues, we often find that communal heating systems, plant equipment and control strategies are contributing more heat into the building than intended. These issues can go unnoticed for months, gradually increasing resident discomfort and energy consumption.

It’s understandable why property managers initially focus on factors such as glazing or solar gain, but it’s important to take a wider view. Before investing in expensive remedial works, it’s worth understanding how the building’s systems are actually performing.

In many cases, the root cause can be identified through a thorough maintenance review, allowing building operators to address the issue more effectively and improve comfort for residents.”

Rupert Mackay, Director, DMG Delta

Why Regular Maintenance Makes All the Difference

Overheating is often a sign of system imbalance or poor maintenance.

Regular servicing helps you:

• Spot issues before they become complaints
• Reduce unnecessary energy use and spending
• Keep residents safe and comfortable
• Stay compliant with upcoming legislation
• Get expert insight before making costly changes

Maintain It’s Heat-Busting Superpowers

When overheating strikes again, there’s no need to call for backup – Maintain It is already on the case.

Armed with years of maintenance, Maintain It’s superpower solutions help uncover the hidden causes of overheating and restore balance to your building’s systems.

His trusted superpowers include:

• BMS reviews and correction
• Pump schedule optimisation
• Lagging and insulation checks
• HIU inspections and servicing
• Root cause investigation with clear, no-jargon reports

These aren’t just quick fixes – they’re proactive maintenance solutions designed to tackle overheating at its source, helping keep buildings running efficiently, residents comfortable, and property managers one step ahead.

Take Control This Summer

If you’ve been fielding complaints, facing eye-watering energy bills, or struggling to explain the sweltering indoor temperatures, now’s the time to act.

Contact us today to speak with our team and find out how we can help you take control of overheating, protect your building, and keep your residents comfortable all year round.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

Introducing The Download

As we step into a new year, we wanted to start by saying a genuine thank you.

Thank you for the questions, the challenge, and the open conversations throughout 2025 – many of them centred around heat network compliance and what it means in practice. They’ve helped shape how we support our clients, the tools we’ve developed, and where we’re focusing our efforts next.

To bring that thinking together, we’ve launched The Download – a new, short-format read designed to share clear insight and practical updates, without adding noise or complexity.

If you’ve got five minutes and a hot drink to hand, the first edition is a great place to begin.

The December issue brings together the themes we’ve seen coming up time and again this year, alongside practical resources to support planning and decision-making.

Inside, you’ll find:

Straight answers to common compliance questions

From early “where do we start?” conversations through to more detailed regulatory queries, we’ve pulled together clear responses you can revisit and share internally.

A clearer approach to compliance support

An explanation of how our compliance services, health checks and support packages are evolving – with a focus on making expectations clearer and next steps easier to action.

Why performance insight matters for heat network compliance

As regulation tightens, heat network compliance increasingly depends on good data, day-to-day visibility and proactive management – not gut feel or reactive fixes.

An updated Heat Network Compliance Companion Playbook

Including the latest HNMF Authorisation Conditions, updated summaries, and new checklists to help you demonstrate control and progress.

Looking ahead to 2026

From bespoke training and podcasts to new ways we’ll be supporting clients through change, we share what’s coming next and how it fits into the wider regulatory picture.

You’ll also find a look back at what we’ve been involved in this year, along with a few lighter moments and end-of-year highlights.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

The Result

The development’s low carbon, high efficiency heating asset was reinstated to benefit residents and key stakeholders.

Heating and hot water services were stabilised across all blocks, with:

• Air cleared from the network
• Flow rebalanced and reverse circulation corrected
• Water quality significantly improved, helping protect the plant equipment and support efficient operation

We also provided the managing agent with clear recommendations to prevent recurrence, including the need for a full recommissioning of the system to secure long-term reliability.

The end result was a restored, fully operational communal heating system, better protected against future breakdowns and inefficiencies, and renewed peace of mind for both residents and the managing agent.

The Most Expensive Room in Your Building – and Why PMs Shouldn’t Avoid It

Let’s be honest — most Property Managers prefer not to spend time in the plant room. It’s loud, full of complex kit, and unless something goes wrong, it’s easy to put to the bottom of the priority list.

But here’s the thing: your plant room is the most expensive and potentially risky space in your entire building. And avoiding it could cost far more than just your peace of mind.

When you’re not sure what’s going on in your plant room, it’s hard to answer resident queries or challenge existing contractors that might be underperforming. You may not know:

• If equipment is working efficiently — or working at all.
• Whether your systems are safe and compliant
• If your maintenance provider is doing the checks they say they are.
• What needs replacing before winter — when failure becomes critical

Avoiding the plant room doesn’t avoid the risk — it just delays it.

In just one hour, you’ll walk away with confidence, clarity, and control.

You don’t have to be an expert – that’s our job.

You’re not expected to know every valve and flue in your plant room. But you do need to know whether your systems are safe, efficient and compliant.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

This article, is part of our quarterly Heat and Maintenance Update series. Each quarter, we share practical insight for property professionals managing communal systems – from overheating risks and system health to energy-saving strategies and resident comfort.

Here’s what’s new, and what to keep on your radar.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

Roasting residents. Soaring complaints. Uninhabitable conditions.

If your building is exceeding 35°C indoors during summer, it’s not just the weather, it’s potentially a maintenance warning sign. And it’s affecting your residents’ health, your energy bills, and your reputation.

In many buildings, unbalanced plant rooms, faulty HIUs or continuous pump cycles are quietly turning up the heat – even in the middle of summer. These aren’t just comfort issues. They affect energy bills, system health and compliance.

At DMG Delta, we help you get to the root cause.

Special Offer for Property Managers – Limited Time Only

Technical Site Reviews – Available Now

We’re offering a limited-time Technical Support Manager Site Review, carried out by a qualified CIBSE consultant.

This includes:

• Full review of your heat network and communal plant room
• Summary report highlighting key overheating risks
• Clear, no-jargon recommendations

Typical cost: £350–£600 + VAT, depending on building size (based on 50–200 units).

Book your Technical Manager review today.

To chat to us about monitoring support, get in touch with our team by calling: 01279 810100.

The Hidden Causes of Overheating in Modern Buildings

Overheating is often assumed to be caused by solar gain – but that’s rarely the full story. In most cases, the building’s own systems are silently turning up the heat.

Here’s what might be going wrong:

• Faulty BMS or controls – Issues like failed sensors, damaged wiring or software faults can affect the operation of the controls
• Unserviced HIUs (Heat Interface Units) – Poorly performing units can drive temperature imbalances across the building.
• Pumps left on override – Without proper cycle control, systems can circulate heat constantly – even when it’s not needed.
• Inadequate insulation (lagging) – Poor-quality or missing lagging means heat escapes into risers and communal areas.
• No shut-off strategy – Some older systems run communal heating year-round, regardless of outside temperatures.

These are all fixable. But left unresolved, they lead to spiralling energy costs, frustrated residents and avoidable wear on your system.

“If you’re managing a building that’s struggling with high indoor temperatures, especially during this heatwave, I’d really encourage you to take a closer look. I recently spoke to a resident who couldn’t sleep – his apartment was over 40°C. That’s not just uncomfortable, it’s unacceptable.

Too often, overheating is blamed entirely on solar gain. But if there’s a communal heating system or heat network present, it may be quietly contributing to the problem. In some cases, I’ve even seen A/C installed to try and counteract it – which simply isn’t sustainable in a net-zero world.

If you’ve got ‘roasting residents’, please don’t assume it’s just the windows. There are practical solutions – but first, we need to understand what’s really going on.”

Rupert Mackay, Director, DMG Delta

Why Regular Maintenance Makes All the Difference

Overheating is often a sign of system imbalance or poor maintenance. 

Regular servicing helps you:

• Spot issues before they become complaints
• Reduce unnecessary energy use and spending
• Keep residents safe and comfortable
• Stay compliant with upcoming legislation
• Get expert insight before making costly changes

We Help You Take the Heat Off

Our specialist teams help you take control of overheating with:

• BMS reviews and correction
• Pump schedule optimisation
• Lagging and insulation checks
• HIU inspections and servicing
• Root cause investigation with clear, no-jargon reports

Whether you need a one-off check or full monitoring, we’ll work with you to reduce the heat – and the hassle.

Take Control This Summer

If you’ve been fielding complaints, facing eye-watering energy bills, or struggling to explain the sweltering indoor temperatures, now’s the time to act.

Book your Technical Manager review or chat to us about monitoring support.

Let DMG Delta help you protect your buildings, your budgets – and your residents.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

Planned maintenance is the backbone of safe, efficient building management. It protects residents, keeps you compliant, and avoids the cost and disruption of unplanned breakdowns. But while most property teams understand the importance of heating checks, one area often gets overlooked: water treatment.

Here’s why routine maintenance matters – and how your water system could be undermining your efforts without you realising it.

Why proactive maintenance isn’t optional

A well-maintained heating system doesn’t just run better. It:

• Keeps people safe – by reducing health and safety risks

• Supports compliance – with audit-ready records and legal coverage

• Prevents downtime – by identifying problems early

• Improves efficiency – saving money on energy and repairs

• Extends system life – delaying costly replacements

• Provides year-round resilience – with plans in place for emergencies

That’s why water treatment isn’t a “nice to have” – it’s essential to system health and resident safety.

Industry guidance supports this. According to CIBSE (Chartered Institution of Building Services Engineers), water quality has a direct impact on energy efficiency, asset longevity and compliance. Their guidance highlights how corrosion, scale and microbial growth in closed-loop systems can lead to costly failures and non-compliance if left unchecked.

In other words: if you’re not actively managing water quality, you’re introducing risk – both financially and from a duty-of-care perspective.

The cost of doing nothing

All systems degrade over time – but without intervention, issues grow harder to manage:

• A minor leak or sticking valve can escalate into a full shutdown

• Ageing equipment can use 20–30% more energy than a well-maintained system

• Legacy parts are harder to find, with longer lead times and higher costs

• Health risks such as carbon monoxide or Legionella increase as control is lost

In short, you’re exposed on every front – cost, compliance and comfort.

Don’t overlook your water system

Even with the best equipment in place, poor water quality can quietly undo everything. Untreated water:

• Corrodes pipework and damages components

• Reduces heating performance and system efficiency

• Allows bacteria like Legionella to thrive in the wrong conditions

Our Water Treatment service helps property managers take control. We test and treat systems regularly, helping you meet safety standards while protecting your assets and your residents. From dosing and filtration to temperature testing and compliance checks – we’ve got it covered.

Ready to talk?

Whether you want a fresh set of eyes or a tailored treatment plan, we’re here to help.

Fill in our quick contact form and we’ll be in touch to talk through your system and next steps.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

At Data Energy and DMG Delta, collaboration powers everything we do – whether we’re delivering expert support for your heat networks or teaming up for a day of friendly competition.

Last week, we brought together colleagues from across both businesses to form the Trinergy Titans, our very own five-a-side dream team, to take part in the News on the Block Footy Tournament.

Swapping laptops for laces and compliance reports for corner kicks, our team took to the pitch for a brilliant day of sport, sunshine and industry connection. The results? One win, two draws and one narrow loss – not a bad day’s work!

More importantly, the event was a great opportunity to meet others in the property sector, build team spirit, and have a bit of fun along the way.

🎥 Catch the highlights in our short video below and see the Trinergy Titans in action.

A huge thank you to our fantastic players across Data Energy and DMG Delta, and to News on the Block for hosting such a great event.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

After months of planning, designing, building (and plenty of sweet-tasting), the TPI Annual Seminar 2025 has officially come to a close – and what a journey it was!

This year was a record-breaking event for us at DMG Delta and Data Energy. From the moment the doors opened, our stand was buzzing, packed with conversations, questions from property managers across the UK.

In line with our Mind the Gap theme, we built a transport-inspired experience designed to bring our heat and energy solutions – and the journey to Ofgem 2026 compliance – to life.

And yes, we may have tempted a few people over with our legendary Pick ‘n’ Mix station. Sweet tooths aside, we were blown away by how many of you stayed to chat about your compliance challenges, billing questions and heat network requirements.

Our competitions and giveaways were a big hit – congratulations to everyone who entered! But beyond the games, what truly stood out were the insightful, honest conversations we had with so many professionals working hard to improve how their buildings are managed.

Whether you were exploring alternative service providers, preparing for regulation changes, or simply curious about how we could help simplify things, it was a pleasure to meet you.

Catch the highlights reel below and relive the energy – or see what you missed!

One Solution, Built for You

Together, DMG Delta and Data Energy provide a complete heat and energy solution for residential buildings. From technical engineering and emergency maintenance to resident-friendly billing and energy procurement, we’re helping property managers bridge the gap between where they are today – and where they need to be tomorrow.

• Building services maintenance and engineering solutions
• Heating, hot water & boiler plant
• Heat networks & energy centres
• Maintenance schedules and emergency breakdown services
• Accurate metering & billing
• Compliance support to keep you one step ahead
• Energy procurement to secure the best deals

📅 Only 367 days until the next TPI Annual Seminar… we’re already on board.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.

Getting You Ready for Ofgem’s New Heat Network Rules:

If you’ve been following the Ofgem takeover story so far, you might be feeling even more confused than before. With 23 authorisation conditions proposed under the new regulations and various webinars and consultations over 2 years, it can be hard to understand the expected outcomes.
Change is tough, and being on the receiving end is even tougher. You’re not alone, many stakeholders still don’t know what’s required – or how to prepare, but we’ve put together the best practice starting points.

We’ve also created a detailed self-assessment checklist, to help you identify gaps and prepare for Ofgem’s new rules. It covers everything from metering and billing to performance monitoring and customer protections so you can confidently prepare for the new regulations. It breaks down what you need to check, where gaps might be and what actions to take to stay compliant.

Key Areas Covered in the Checklist:

• Metering and Data Collection: assessing the installation and functionality of meters and data recording systems.
• Tariff Setting and Billing: ensuring tariffs are fair, transparent, and reflective of actual costs.
• Maintenance and Performance: establishing protocols for regular maintenance and performance audits.
• Consumer Protection Measures: implementing systems to safeguard consumer interests and support vulnerable residents.

Taking a proactive approach now will help mitigate risks, avoid costly penalties and ensure seamless operations in an increasingly regulated market. Many of the next steps are straightforward wins, and in some cases, your billing or maintenance provider may already be covering key requirements. Compliance isn’t something to put off – it’s here to stay – but you may find that achieving it is far simpler than you initially expected.

Download Part 2 of our E-Guide and get access to your self-assessment questionnaire.

We understand how complex and time-consuming it can be to sift through all the regulatory information, so we’re here to make it easier for you. We’ll regularly analyse the latest updates and provide simplified, actionable insights through podcasts, webinars, articles and guides.

Our goal is to give property managers the clarity and confidence they need to focus on their day-to-day responsibilities, knowing they have an expert guide by their side every step of the way.

Sign Up and Stay Ahead with Expert Guidance for Property Managers

Regular updates, insights and exclusive access to our industry events:

• Straightforward guidance and expert insights on the latest heat network regulations and what the changes mean for property managers.

• Exclusive access to resources and events. Be the first to access our podcasts, webinars, checklists, useful links, resources and downloadable guides.

• Practical tools to help you stay compliant and confident, including regular reminders of the tasks you need to tackle to stay on track.