A breath of fresh air

Eliot Warrington of Solarcrest argues that building regulations need to reflect 21st century ventilation.

Building Regulations have pushed people in the UK closer and closer towards airtightness in recent years, but while this is a demonstrably good thing with regards to the efficiency of heating your home, they seem to have ignored an important element of every building – ventilation.

The Victorians knew that it was important to allow fresh air to replace all of the smoky dampness you would get from boiling a kettle on the fireplace, so Victorian homes were designed to draw stale air up the chimney, with replacement air being drawn in through inherent gaps in the building fabric. Current regulations assume that ventilation technology hasn’t improved since. There have been some changes in the way things are done, of course. We have compensated for less leaky building materials by introducing trickle vents in window frames, and mechanical extractor fans instead of open chimneys for example, but the end result is the same. You must have holes in your property for the specific purpose of letting ‘fresh’ air in, even though the rest of your home needs to be airtight!

When you add up the combined ‘free area’ of all the trickle vents required to let adequate amounts of air in, you’re looking at a hole typically over one square foot for a small three-bed home – effectively the size of an open window. If you close the trickle vents to stop draughts, your ventilation simply doesn’t work. You can’t extract air from an airtight box without the means of replacing the air being extracted.

Ventilation is even more important today given indoor and outdoor air quality issues, even if the regulations haven’t advanced much from the 19th century to the 21st. The recent drive to better insulate people’s homes for environmental reasons is all very well, but a lack of forethought and knowledge about ventilation has led to new problems. Insulation might well reduce fossil fuel consumption and with it CO2 emissions, but ventilation doesn’t, so funding for ventilation hasn’t happened because it doesn’t help anyone meet CO2 targets. Well-insulated but under-venti- lated homes trap damp, which leads to mould and then poor health. The problem has become common enough for a small industry to spring up to help homeowners gain compensation for having had their home insulated. Insulation providers are becoming the scapegoat when Government policy is to blame.

Inadequate ventilation has now been shown to cause more than cosmetic problems for home owners. Black mould has been linked with respiratory problems in children, and recent research in Wrexham and New Zealand has shown that not only could mould exacerbate the symptoms of asthma, but it could also be linked to triggering a child’s first attack, meaning that ventilation isn’t only vital for the health of your home.

External pollution can also come into play. Millions of hay fever sufferers in the UK look forward to the summer with a mixture of hope and dread. At the same time the more serious issues of poor air quality and pollution from diesel engines are causing serious health problems, particularly in the cities.

Fixing the problem

While Building Regulations might be stuck in the past, the technology available to fix the problem has progressed significantly.

Mechanical Ventilation with Heat Recovery (MVHR) is a simple enough concept. It’s a machine which includes a series of ducting pipes that extracts damp air from wet rooms like the kitchen and bathrooms, without wasting the heat that’s in the air. Instead it uses the heat from the stale air to warm fresh air which is being drawn in. Usually situated in an attic or plant room, the MVHR unit will also filter fresh air to remove pollen and dust, with some top-level units even offering filtration powerful enough to remove the tiny diesel pollution particles, too. The technology is nothing short of a game- changer when it comes to air quality.

So once you have identified that you want to move into this century with your ventilation, what next?

First, you need to make sure you take it into account in your planning. While the systems can be installed into properties which are already occupied, and this would actually help cure the problems caused by poorly insulated airtight homes in the past, it’s easiest to install during the build. The ideal time to minimise any interruption to the rest of the process is just before the electricians and plumbers arrive, so it’s important that you have this in your thoughts from early in the planning process.

It’s also important to remember the old maxim that, as with anything, you get what you pay for. The cheapest system on the market is cheap for a reason. When you are building, you don’t want to cut corners on comfort or end up with something noisy. If people advise against it, because ‘you can get through Regulations without it,’ think about what residents could be missing. Imagine building a car to spend over 12 hours a day in for the next 10 years. In terms of features, climate control would be a no brainer. So now it’s available for homes too, why miss out just because its not mandatory under regulations?

It’s time for building control to change, you can’t demand airtightness as well as holes in every window frame. It doesn’t make sense. Look again at the benefits of 21st century ventilation, set higher minimum standards, and do what’s best for homes and the people who live in them.

Eliot Warrington is managing director at Solarcrest.