RELY ON US FOR OVERHEATING CALCULATIONS IN THE UK
Ensure your new build or conversion is compliant with Part O regulations. Expert Energy Consultancy Ltd in Sheffield provides accurate overheating calculations, helping design comfortable and cool spaces.
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Contact us for reliable and tailored assessments.
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GET PART O ASSESSMENTS
In the face of rising temperatures, Part O (England) Section 3 Overheating of the Building Regulations was introduced to combat overheating risks in residential buildings. At Expert Energy Consultancy Ltd in Sheffield, we provide detailed overheating calculations with particular attention to vulnerable occupancies to ensure thermal comfort and safety during periods of hotter weather.
Our team performs comprehensive assessments of solar gains and ventilation strategies, offering solutions like solar shading, openable windows, and dynamic thermal modelling when needed. Whether you’re working on a new build or conversion, we ensure your space remains cool and energy-efficient. Contact us today for your Part O compliance check and a free consultation.
WHAT IS PART O?
Approved Document O (Part O) was introduced to address the increasing risk of overheating in residential buildings, particularly during hotter weather. The regulation ensures that homes are designed to maintain safe and comfortable internal temperatures without the need for active cooling systems.
Part O applies to:
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Newly built dwellings
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Conversions to residential use
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Buildings with high glazing ratios or limited cross-ventilation
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This regulation became a legal requirement in England in June 2022. If your project falls under any of the above categories, you must demonstrate compliance to gain Building Control approval.
DYNAMIC THERMAL MODELLING
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Send us your drawings, elevations, orientation & glazing layout for an initial comment on risk rooms.
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Build 3D digital model of property in line with the SAP calculation, & test the following until we reach a pass.
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Run simulation to as designed Natural Ventilation.
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If there are no critical fails, we will run a second time by manipulating existing openings before moving onto MVHR.
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We will model the flow rates of the MVHR supply & extract per room, if this is on top of improving glazing G value & solar shading isn’t enough to cool the property this will justify to air con.
WHAT DO OVERHEATING CALCULATIONS ASSESS?
Overheating calculations under Part O focus on two main performance criteria:
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Limiting Solar Gains: This involves assessing how much solar heat enters the building through windows and glazed areas, particularly on south- and west-facing elevations.
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Providing Adequate Ventilation: We evaluate how well your design allows air to circulate and cool the space naturally.
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To demonstrate compliance, we use either:
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The Simplified Method: Suitable for straightforward, smaller residential designs
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Dynamic Thermal Modelling (DTM): required for more complex developments or properties located in high-risk areas, such as Greater London.
OUR OVERHEATING ASSESSMENT SERVICE
We offer a full Part O assessment service to support your project from early-stage design to final submission. Our process includes:
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A full review of architectural drawings, elevations, orientation, and glazing layout
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A detailed risk assessment based on solar gain, ventilation strategy, and site location
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Tailored advice on meeting compliance might include using solar shading, increasing window opening sizes, or adding mechanical ventilation.
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Simplified Method analysis or complete Dynamic Thermal Modelling, where required
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A clear, fully compliant report ready for submission to Building Control
WHEN IS DYNAMIC THERMAL MODELLING REQUIRED?
You may need a more advanced overheating assessment using Dynamic Thermal Modelling (DTM) if your development includes any of the following:
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It is located in a designated high-risk zone (e.g., any London borough)
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The building includes mechanical cooling or ventilation systems
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There are single-aspect flats or rooms with limited window openings
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The project is a larger-scale development with varying layouts and unit orientations
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A major advantage is that, in addition to its precision, this method is also more flexible in its assessment, considering a wider range of factors. Whereas the simplified approach is more rigid and typically results in a straightforward pass or fail outcome.
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Dynamic modelling offers a precise simulation of internal temperatures and performance, giving Building Control confidence in your project’s ability to manage overheating risks.
