Building Regulations for new housing require ever-higher levels of energy efficiency. The best way of achieving this is by using increasing levels of insulation to the point whereby a house is virtually airtight. However, an airtight home can be an unhealthy place to live with stale air, foul smells and condensation. This is where Mechanical Ventilation Heat Recovery (MVHR) can make a difference. A heat recovery unit will make a significant contribution to producing a low energy, eco-friendly building with high insulation and air tightness levels.
A Heat Recovery Ventilation system (HRV) is a ventilation system that removes polluted air and replaces it with a supply of clean air. New homes equipped with a Mechanical Ventilation Heat Recovery system have a healthy indoor environment, provided the filters are maintained and replaced when necessary.
The Mechanical Heat Recovery device of the MVHR system draws air into the building from the outside, filters it, takes it through a heat exchanger and supplies the clean air into the habitable spaces of the house, usually bedrooms, living rooms, studies etc. A completely separate ducting system extracts air out of the foul air rooms (toilets, bathrooms, kitchens etc.) through the other side of the same heat exchanger and exhausts it out of the building. This enables a balanced ventilation system where you are supplying exactly the same quantity of air into the building as you are extracting out of it.This system is unique to new homes as it is almost impossible to apply this new system to old buildings; unless it is a complete rebuild. With a balanced ventilation system using HRV an estimated annual saving of 250m3 of gas can be made.