What Causes Poor Ventilation

Modern homes are designed with energy efficiency in mind.  High quality insulation, and close-fitting windows and doors help to make the building almost airtight.  Preventing draughts and heat loss is important in avoiding waste and reducing energy bills but creating a barrier to airflow has the consequence of increasing humidity as moist air cannot escape.

Trapping moist air in your home results in condensation forming on walls and windows and this can lead to problems developing with damp and mould growth that can damage the fabric of your home and increase health problems.

Improving the ventilation in your home will help to reduce the presence of condensation and the attendant damp problems that it causes.

Simple steps to improve ventilation

If your home has poor ventilation, then the simplest change you can make is to open windows and interior doors to allow air to flow through the house.  This will refresh the air in your home, but it comes at a cost: 

Having windows open means that all the effort you have gone to while improving insulation and energy consumption is wasted, and you will also allow noise and pollutants, as well as pollen, into your home which can cause irritation.

Leaving windows open, can also be a risk to safety and security.  An open window, even a relatively small one provides a means of access to unwanted guests, and could also be an opportunity for a child to fall.

Ventilation Systems

Going beyond basic extractor fans which are designed to operate in a single room such as a kitchen or bathroom, whole house ventilation systems are a highly effective way of improving airflow and air quality throughout a home and preventing problems like condensation and damp from arising.

There are two main types of whole house ventilation system available and while both improve airflow throughout the building, they work in subtly different ways and are suitable for different types of property:

• Positive Input Ventilation
• Mechanical Extract Ventilation

Positive Input Ventilation

PIV systems work by drawing air into a building from outside and then distributing it into the house from a central unit that is usually mounted in the loft or a cupboard.  Air is drawn in at roof level, to avoid ground level pollution.  PIV systems include air filtration that prevents pollen from being drawn into your home.  The slight increase in indoor air pressure caused by the PIV system effectively pushes the stale moist air out of the building natural gaps in the home.

PIV systems are commonly fitted into existing properties by specialist engineers.

Mechanical Extract Ventilation

MEV systems effectively reverse the airflow of a PIV system.  Rather than relying on drawing air into the building to push out stale air, they function as a whole house extractor system, and push air out of the house to be replaced by fresh air from outside which again is filtered to ensure that it is free of particles.

MEV systems are more complex to fit, and are normally installed in new-build properties, or as part of a bigger refurbishment.

Heat Recovery can be a part of an MEV system (MVHR).  MVHR removes the heat from air that is being extracted from the building and uses it to heat the incoming air.  MVHR systems are highly efficient and can recover between 60-95% of the heat in exhaust air.

Find out More

To learn more about how whole house ventilation systems such as PIV and MEV can help improve the air quality in your home, please contact us today to arrange a survey from one of our local ventilation specialists.  They can visit your home and provide advice about the best solution for your needs.