Building Regulations – A better understanding
The purpose of the regulation is to ensure 'adequate means of ventilation is provided for people in the building’, improving building performance and indoor air quality for occupants of both new and existing dwellings in the UK.
By providing outside air to breath, ventilation assists in the dilution and removal of pollutants as well as reduction in humidity/condensation, which combined create a more pleasant environment and relief for asthma and allergy sufferers.
In short, ventilation provides fresh, clean air reducing the health risks to people and protecting the building fabric from damage.
The changes in energy efficiency regulations require buildings to be 'better sealed' and 'more airtight'. The new Part F Document provisions have been designed to ventilate buildings having air permeability down to 3m³/h/m² at 50 Pa, allowing designers to plan to ‘worst case’ as Buildings Regulations document Part L allows air permeability up to 10 m³/h/m². The remainder of the document allows the designer plenty of flexibility on how to comply with the regulation as an element of the Decent Homes standard.
At the same time, the changes reflect the most recent research, linking air pollutants and condensation to effects on health (particularly asthma) and damage to the building fabric (mould), with guidance on ventilation systems and required flow rates taking this into account.
The part F document provides guidance on ventilation system options these are:
The Ventilation Options
- Background ventilators and intermittent extract fans
- Passive Stack Ventilation
- Continuous Mechanical Extract (MEV)
- Continuous Mechanical Supply and Extract with Heat Recovery
- 0.15 Other ventilation systems and devices, perhaps following a different strategy (e.g. positive input ventilation ) may provide acceptable solutions provided it can be demonstrated by way of a BBA certificate that they meet the requirement F1.
