Mark Chesney from Beam Vacuum & Ventilation explains how houses have become increasingly airtight and why this has had a significant impact on energy efficiency. He also shares why having a good ventilation strategy is so important.
Interview with Mark Chesney
Mark Chesney is the Installation and Services Manager at Beam. For 15 years the company has been fitting ventilation products into new and existing homes as part of energy saving measures and to provide clean indoor air.
Ventilation Products are for All Homes
Mark believes this is applicable whether the homes are decades old or airtight new builds.
There are Three Parts of a Building That Need Ventilation
- The living space
- The structure
- Where there might be combustible appliances, such as fires and stoves etc.
Mechanical Ventilation is Required on More Airtight Buildings
Historically, mechanical ventilation hasn’t been required as buildings have had so much natural leakage within the frame of the house. With the ever rising costs of fuel to heat homes, far more consideration is being given to creating more airtight dwellings, and with this is the need for mechanical ventilation to allow the people within the home to breathe more easily and allow for better air change.
The Cheapest Way to Ventilate a Building is to Open the Windows!
Obviously the drawback of natural leakage and opening windows to ventilate buildings is that you can’t control the cold ingress from outside or the heat loss to the outside.
This method of natural ventilation progressed to trickle vents and independent extract fans to more modern mechanical extract systems and ultimately the Mechanical Ventilation with Heat Recovery (MVHR) systems that are now recognised as an essential part of an airtight home.
The Number of Air Changes Per Hour Will Impact on the Building’s Ability to Retain Heat
If you were to ventilate a domestic home with 4 air changes per hour you would struggle to retain heat within the home. The recognised rate for a new build would be closer to just less than half an air change per hour. A Passivhaus is even less at .3 changes per hour.
Setting a new home to have one air change every two hours will greatly reduce or eliminate condensation and mould, and provide a fresh air climate. Most of the products will also filter the air to some degree.
The Airtightness of the Home Will Help Determine the System to Use
Things to consider when choosing a system are, the number of people living in the home, its airtightness, and whether it is well insulated enough that it warrants an MVHR system. Sometimes a simpler system will be an approved alternative in an older and less airtight retrofit.
The heat within a Passivhaus equipped with MVHR system will be retained much more easily than in a traditional dwelling, which even with a low air permeability rating and high levels of insulation, is still going to need a primary heat source.
A Central Vacuum System is Independent of a Ventilation System
At Beam, they provide both central vacuum systems and ventilation systems which, while being standalone products, both have the combined aim of providing cleaner air and a better indoor climate for everybody, with particular benefits to those suffering from asthma or allergies.
The central vacuum system works by drawing out dust through special wall sockets, along a lightweight hose and out via a motor located in a non-living area of the house.
Airtightness is Now an Integral Part of House Building in Northern Ireland
Mark believes that with the greater range of airtightness products available on the market over the last decade, the construction industry in Northern Ireland has adapted to such an extent that nowadays everyone involved at each phase takes it on board to ensure that houses are being built airtight and built better.
Find Out More
The Future of Housing – Premiere
This week we completed the filming of our crowdfunded documentary The Future of Housing – And How Airtightness Can Help. Next stop: the edit!
So if you want to attend the London premiere, don't delay because there are only 50 tickets left!
The launch takes place on Thursday 4th December 2014 at the Mildmay Community Centre and there are already some big names from the green building world booked in!
Be part of our special evening – get your ticket now.