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Overheating is rapidly becoming a major issue for residential building designers.

The tendency for new build dwellings - especially apartments - to reach uncomfortable temperatures during summer is an increasing problem in need of a solution.

Overheating makes sleep uncomfortable, causes heat stress, and in severe cases, presents serious health risks.

What causes overheating?

Historically, hot outdoor temperatures and glazing have been the main causes of overheating in residential dwellings. Sunlight streaming through windows heats internal surfaces, furnishings, and inside air, but is unable to escape back through the glass.

What Causes Overheating in New-Build Dwellings?

What is the typical solution?

Natural ventilation would usually be a simple fix, providing cooling via openable windows. But often external sources of noise and air pollution mean opening windows are not an option.

Approved Document O

What does Approved Document O suggest?

Approved Document O outlines various overheating mitigation measures to help combat the issue of overheating in dwellings. Some of the recommended methods include:

  • Reducing overall glazing
  • Providing solar shading
  • Natural ventilation via openable windows
  • Cross ventilation

But what options do building designers have when these methods have been exhausted, but the problem of overheating remains?

What is the last line of defence against overheating?

MRXBOX Hybrid Cooling System In Situ

Our solution

Nuaire's new MRXBOX Hybrid Cooling System combines year-round levels of indoor air quality, with the added benefit of summer cooling to mitigate overheating.

Working in conjunction with coolth recovery from the heat exchanger, this added cooling from the cooling module significantly lowers the temperature of fresh air supplied into the dwelling. This helps maintain comfortable internal temperature levels, even in city centre apartments on the hottest days of summer.