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An overheating risk assessment is essential in addressing the industry gap with regard to overheating assessments. Situations, where the internal temperature is unreasonably high, must be identified as quickly as possible so that actionable changes can be made to counteract the issue.

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Homes that overheat are at risk of posing a significant threat to the safety, health and well-being of those inside. With ongoing and upward-trending temperatures and trends in modern architecture, internal temperatures are reaching all-time highs in the summer months.

Focus 360 Energy understands the importance of rectifying these issues of overheating as quickly as possible for both the health and safety of residents but also for the cost-effectiveness of making changes to a building.

Safeguard inhabitants and your project with a TM59 overheating assessment from the specialists here at Focus 360 Energy.

What is TM59?

The assessment of overheating risk in homes was developed and published by CIBSE in 2017. The aim was to address the industry gap concerning overheating assessments of residential properties. Before the TM59 was developed, there were no specific industry criteria to base overheating in homes. As such, energy assessors and consultants would likely use differing model setups with no real benchmark on which to base the results.

Overheating Risk in Homes

Houses built prior to the early 1980s typically lacked insulation. With evolving standards and improved materials, today’s buildings boast much-improved insulation. Modern constructions also prioritise better air permeability.

Contemporary buildings frequently feature large glass facades. While this is advantageous for preserving warmth in colder seasons, it can pose a challenge in the warmer months, potentially leading to overheating issues.

Reasons Why a Home Could Overheat

Several factors contribute to the risk of overheating in homes. Homes with extensive glazing, especially south-facing windows, are susceptible to absorbing and retaining heat. Ineffectively designed natural ventilation, along with low air permeability rates, can hinder the proper circulation of air, exacerbating overheating concerns. Insufficient thermal insulation, low thermal mass, and single-aspect designs can also contribute to temperature imbalances. Additionally, properties connected to community heating systems and new builds may face challenges in regulating internal temperatures. Recognising these elements is crucial for implementing effective strategies to maintain a comfortable and well-ventilated living environment.

Often coupled with:

SAP Calculation - New Build
Energy Statement
Energy Statement - London Plan
Air Pressure Testing
Flood Risk Assessment
BREEAM Assessment
Water Consumption Calculation (Part G)

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Standards Used in TM59

TM59 by CIBSE outlines a method for evaluating expected internal temperatures in residential-only properties. It provides essential data for energy modellers, such as occupancy hours, internal heat contributions from equipment in various rooms, and heat generated by occupants.

The standards also offer recommendations for determining when to open windows based on internal air temperatures. Additionally, they suggest heat gain considerations for hot water pipework traversing living spaces or communal areas like apartment corridors.

The guide establishes specific criteria to demonstrate compliance and mitigate the risk of overheating. These criteria focus on the duration the internal air temperature exceeds predefined levels, addressing both daytime and nighttime occupancy to ensure comfort during sleep.

When Should I Carry Out a TM59 Assessment?

Conducting a TM59 assessment holds utmost importance during the design phase of a new project. This evaluation becomes a crucial tool to ensure that your initial design aligns with the necessary requirements to prevent overheating in your building.

Initiating a TM59 assessment at the design stage is vital. If the preliminary design falls short of meeting the stipulated requirements, this early assessment allows for adjustments before the commencement of construction. Potential alterations may involve resizing windows, enhancing window opening capabilities, adjusting glass specifications to mitigate solar gain, or even modifying room sizes and orientations.

What Properties Should Have a TM59 Assessment?

TM59 overheating assessments prove invaluable for evaluating the risk of overheating in new residential properties, especially large developments or those emerging in urban settings.

The assessment is particularly relevant for diverse structures such as Care Homes, Student Accommodation, and single-aspect flats, where high insulation levels and air tightness may lead to overheating concerns. It is essential to extend the evaluation to individual rooms within these buildings, including spaces that are mechanically ventilated. For instance, assessing the living room in your house is crucial, ensuring a comprehensive understanding of the potential overheating risks.

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Why Choose Focus 360 Energy for your TM59 Assessment Needs?

At Focus 360 Energy, we stand out as industry leaders in delivering unparalleled excellence in energy assessments. Here’s why discerning businesses choose us for their energy efficiency needs:

Expertise That Matters
Our team comprises seasoned professionals with an in-depth understanding of TM59 requirements. We bring a wealth of knowledge and experience to ensure your assessment is conducted with precision and insight.

Tailored Solutions
We recognise that every building is unique. Our approach is not one-size-fits-all. We tailor our TM59 assessments to address the specific needs of your property, ensuring maximum impact and compliance.

Cutting-Edge Technology
Leveraging state-of-the-art technology, we conduct thorough energy assessments, providing you with detailed insights into your building’s energy performance. This enables us to recommend precise strategies for improvement.

Cost-Effective Strategies
We believe in delivering value. Our TM59 assessments not only focus on compliance but are also designed to optimise your energy consumption, leading to long-term cost savings for your business.

Client-Centric Approach
Your satisfaction is our priority. We work closely with you throughout the TM59 assessment process, keeping you informed and involved. Our client-centric approach ensures that your unique requirements are met with dedication and precision.

Choose Focus 360 Energy for your TM59 assessment and embark on a journey towards enhanced sustainability, cost savings, and regulatory compliance. Contact us today to experience the Focus 360 Energy difference.

Get Expert Assistance

Are you ready to revolutionise your building’s energy efficiency? Take a transformative step with a TM59 assessment and unlock the full potential of your property. Our seasoned experts are prepared to guide you through a comprehensive process, ensuring not only compliance but also substantial cost savings. Begin with a consultation to discuss your unique needs, followed by a detailed assessment of your building’s energy dynamics.

Frequently Asked Questions

What is a TM59 Overheating Assessment?

A TM59 Overheating Assessment is a thorough evaluation of the risk of overheating in residential properties. It was developed by CIBSE to address the lack of specific criteria for assessing overheating in homes. The assessment helps identify situations where internal temperatures are unreasonably high, allowing for actionable changes to counteract the issue.

Why is a TM59 Assessment important for my building?

TM59 Assessments are crucial for ensuring the safety, health, and well-being of occupants. Homes that overheat pose significant threats, especially with rising temperatures and trends in modern architecture. Identifying and addressing overheating issues can safeguard inhabitants and improve the cost-effectiveness of making changes to a building.

When should I consider getting a TM59 Assessment?

Conducting a TM59 Assessment is most effective during the design phase of a new project. By assessing the risk of overheating early in the design process, adjustments can be made to prevent issues before construction begins. This can involve resizing windows, enhancing ventilation, or modifying room sizes and orientations.

What types of properties should undergo a TM59 Assessment?

TM59 Assessments are particularly relevant for new residential properties, especially large developments or those in urban settings. They are also beneficial for diverse structures such as Care Homes, Student Accommodation, and single-aspect flats, where high insulation levels and air tightness may lead to overheating concerns.

How can Focus 360 Energy help with my TM59 Assessment needs?

Focus 360 Energy is a trusted industry leader in energy assessments. We offer expertise, tailored solutions, cutting-edge technology, and cost-effective strategies to ensure your TM59 Assessment is conducted with precision and insight. Our client-centric approach ensures your unique requirements are met, leading to enhanced sustainability, cost savings, and regulatory compliance.


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