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Complement your Passivhaus certification with 3D modelling

Passivhaus is widely regarded as the ‘gold standard in energy efficiency’, characterised by exceptionally low operational energy demands and high levels of indoor environmental quality.  

The standard limits space heating capacity to just 10W/m², or 15kWh/m²/annum. It achieves this through tight controls of energy transfer across the thermal envelope and passive solar heat gain. Public authorities in the UK are striving to obtain Passivhaus certification as part of their net-zero carbon and energy efficiency targets.

However, the Passive House Planning Package (PHPP) used for certification does have its limitations, particularly where non-domestic buildings with complex HVAC systems are concerned. 

This is where IES Consulting can help.

Our Complementary Services

With over 20 years’ experience using the world-leading Virtual Environment (VE) technology, our expert consultants are ideally placed to provide complementary services to support and enhance your Passivhaus scheme. The application of a VE model can help designers limit risks, optimise performance, and undertake performance assessments beyond the limitations of the PHPP.

A VE Dynamic Simulation Model allows designers to:

  • More accurately predict daily, seasonal & annual solar irradiance on their concept stage designs. In turn, this can help optimise designs for passive solar heat gain, daylight availability and summertime thermal comfort.
  • Detect localised overheating risks using highly granular data.
  • Simulate complex HVAC systems to high levels of accuracy using the IES ApacheHVAC module, accounting for zonal modelling, complex system controls, performance curves, and more. 
  • Accurately simulate the impact of thermal mass within a design and evaluate its interaction with ventilation strategies (e.g. night-time purge ventilation).
  • Evaluate the impact of daylight dependant lighting controls.
  • Evaluate performance of the building under predictive weather scenarios.
  • Output performance data in sub-hourly time steps (as low as 1-minute time steps).
  • Evaluate daylight performance and indoor air quality.
  • Assess performance against a range of industry metrics, including BB101, CIBSE TM54, CIBSE TM52 & TM59, BR’s Part L2A, and various BREEAM credits.

Modelling for Safer Workplaces

Fresh air ventilation is crucial for reducing the risk of Covid-19 infection. However, increased ventilation rates can pose challenges for Passivhaus buildings. With the help of a 3D IES model, IES Consulting can assist you in optimising ventilation strategies for performance, whilst limiting ventilation fan loads, accounting for natural ventilation, shading, detailed HVAC modelling, building orientation, and occupant comfort. For even higher levels of design detailing, we can also assist with CFD analysis.

Post-Occupancy Monitoring & Calibration

Typically, the ‘performance gap’ of Passivhaus dwellings is particularly low. The correlation between designed and actual performance is especially close by comparison to conventional compliance routes. However, non-domestic buildings do not always share this benefit.

Post occupancy monitoring of such buildings can therefore be beneficial, to ensure that the design intent is achieved in practice. IES Consulting can develop a Digital Twin of your operational building to continually monitor your building's operational efficiency and identify any areas where it is not performing as it should. Using this data, we can provide solutions to help align operational performance with the designed performance as necessary.