Buying a new house, or having one built, can be an exciting time for any new homebuyer with so many things to consider … bench surfaces, appliances, wall colours, tile choices, carpet colours … the list goes on. And it’s no news that today’s homebuyer is more discerning than ever - not just about the aesthetics of their new home - but also about how the home will function as a safe and healthy environment for their family. In recent years there has been an increased focus on homes, old and new, being well insulated and airtight. A well-insulated home offers its owners increased energy savings and - more importantly - protects against asthma and other respiratory illnesses.
But are well-insulated, airtight homes enough to satisfy today’s discerning home buyer?
In addition to good insulation it is vital that homes be well ventilated to prevent excess moisture from building up. The New Zealand climate is often cold and wet, particularly in the winter, making it impractical to open doors and windows for ventilation. Showers, un-flued gas heaters, cooking and even breathing creates moisture, leading to a damp interior.
Condensation is the visible symptom of stale, unhealthy air in homes. Most homes provide the perfect breeding ground for mould - which thrives in high humidity. Over two thirds of New Zealand homes have mould or mildew present - with the Upper North Island judged as the worst! Another consideration is the amount of moisture a new home can produce. Concrete slabs contain several thousand litres of water and can take an average of one month per 25mm of slab thickness to dry completely.
What does a home ventilation system actually do and why would I include one in my new build?
Home ventilation systems use fans to move air into the house, providing continuous ventilation regardless of the weather and without the need to open doors and windows. This helps to maintain air quality and remove moisture from everyday living activities. A well designed and installed home ventilation system offers the convenience of good ventilation by delivering required air replacement continuously and independently of weather conditions. Independent research undertaken by Massey University shows that home ventilation systems do in fact reduce fungal spores, moisture and carbon dioxide, making a home drier and healthier.
Occupants tend to experience fewer headaches, sneezing and eye irritations, and over time fungal spore levels are greatly reduced. Drier homes can be heated more effectively and are more durable – protecting the owner’s investment.
There are two types of home ventilation system to consider:
Positive pressure ventilation systems - draw fresher, drier air into the home from either the roof cavity or outside. This air is then passed through a high efficiency filter and introduced into the home. This introduced air forces out the moist, stale air that causes condensation, mould and mildew. Balanced pressure/energy exchanger ventilation systems - use the energy the household has paid for, say to heat the lounge or cook meals, passing it through an advanced energy recovery converter and tempering the fresh, dry air from outside before moving it to rooms that need it most. Which system is best depends on the design of the house, its floor area, how much sun the house receives during the day, the type of roof and the local climate.
Note: Beacon Pathway research has found that systems that are not controlled by humidity sensors can at times increase moisture levels within the house. For best moisture removal performance look for a system that considers both temperature and humidity of the supply air and inside the house to control the system.
A variety of studies from different organisations show improved health and comfort benefits as a result of the installation of a home ventilation system. As consumers become more aware, home ventilation systems are fast becoming an important inclusion for any new build.
Editors Note: This is a guest post submitted on behalf of SmartVent