Part F – Ventilation Calculations

Part F Ventilation Calculations
Part F Ventilation Calculations

Part F Ventilation Calculations Assessed with Part L (Energy)

Mechanical ventilation is often needed to meet Part F ventilation requirements. For example in situations where cross ventilation isn’t possible such as single aspect flats, and for dwellings where excessive noise from the outside requires certain windows to be closed at all times.

Through integrating the calculation of ventilation with the SAP, using technical experts such as those in our energy consulting team, you ensure the most appropriate system is specified in a dwelling and in so doing, reducing the overall costs of your project.

Better Ventilation Standards

Need for Part F Ventilation Calculations has come about following an increase in the amount of mechanical ventilation being specified in domestic properties. This has largely come from Building Regulations, creating ever more ambitious targets for reducing energy consumption and CO2 emissions, resulting in stricter requirements for air tightness.

In 2011, BSRIA undertook performance tests and found 95% of systems failed to meet the airflow rates set out in Building Regulations guidance. Poor assessment results in ventilation systems being under-specified and reduces the value of a property to a prospective buyer, or over-specified at an increased cost to the developer.

Proven to Reduce Overall Costs

Significantly, ventilation of any sort also affects the Dwelling Emission Rate and energy consumption in Part L of Building Regulations, and mechanical ventilation can be used to reduce the emissions and energy consumption.

Following our consultation, one of our long-term clients, a large UK house builder, has recently updated their build specification to include decentralised mechanical ventilation (dMEV) systems on house-types that failed to achieve Part L compliance. The solution has reduced overall costs through omitting renewables. 



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