For many years, homes in UK N. Ireland and Ireland have been ventilated
via natural air infiltration. The result of this has been high energy
consumption for space heating (which accounts for over 50% of the energy used
within a dwelling).
New energy efficient homes today are being built as airtight as possible through double or triple glazed windows, sealed doors, high levels of insulation and contributing towards enhanced u-values. Existing property homeowners are being encouraged to make homes more energy efficient by insulating their roofspace, cavity walls etc.
This increased airtightness in a dwelling requires a planned ventilation approach. The objective of a good ventilation strategy is to provide a balance between energy efficiency and indoor air quality. This strategy should have an integrated approach, taking into account other factors such as thermal insulation, heating systems, controls and the requirements of the household occupants.
According to The Energy Saving Trust, “energy loss due to ventilation accounts for approximately a fifth of space-heating energy demand in an older poorly insulated dwelling. Natural air infiltration alone can result, at times, in too little ventilation. This leads to poor indoor air quality and other, more readily visible impacts such as condensation and mould on indoor surfaces”.
Add to this the fact that poor ventilation in a dwelling can also cause potentially serious health issues, excessive carbon dioxide, damage to the fabric of the building and it’s easy to see why the concept of “Build Tight – Ventilate Right” has never been stronger.
Presently ventilation (required by Building Regulation) in houses is provided by: