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.

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