On Saturday 03 June 2017, the Financial Times Weekend published a feature on Healthy Buildings with interview content from David Gale.
Architect: Gale & Snowden Architects Ltd. Photograph: The Modern House |
Below is the article by Carl Wilkinson in its entirety:
In his 2008 book In Defence of Food, Michael Pollan set out his “Eater’s
Manifesto”. It included: “Don’t eat anything your great grandmother wouldn't
recognise as food” and “Avoid food products containing ingredients that are a)
unfamiliar, b) unpronounceable, c) more than five in number”. We could apply
the same rules to the materials we use in our homes.
While interest in healthy food has grown, we still live in homes built
from materials that our great-grandparents would be hard-pressed to recognise
and containing ingredients most of us could barely pronounce. Now, a handful of
architects, designers and companies are questioning the impact of these
materials on our health.
Three years ago, David Gale, director of Gale & Snowden Architects
in Devon, co-founded the non-profit Building Biology Association — the UK affiliate
of the Institute of Building Biology and Sustainability, founded in Germany in
1983. “At the heart of Building Biology,” he says, “lies the notion that nature
is the golden principle that we should be designing our buildings to so that,
for instance, air and water quality and electromagnetic radiation levels should
match nature as closely as possible.”
Gale argues that as homes become more energy efficient, they can also
become less healthy. “If you make a building more airtight, badly ventilated
and have lots of toxic chemicals in it, you’re going to have problems.”
The research backs him up. A 2014 study by the University of Exeter
Medical School found that the greener a home, the less healthy it could be. It
concluded that “a unit increase in household Standard Assessment Procedure
rating” — the measure of a home’s energy efficiency on a scale of zero to 100 —
“was associated with a 2 per cent increased risk of current asthma, with the
greatest risk in homes with SAP greater than 71”. New homes in the UK have an
average rating of almost 80.
“We’re designing homes and schools where there are no windows that
open,” says Amena Warner, head of clinical services for the charity Allergy UK.
In a well-sealed environment, temperatures and humidity can rise to create the
ideal environment for allergens such as the house dust mite and mould. As a
result, Warner says occupants “might get allergic rhinitis — a blocked or runny
nose — and they can also get asthma. We know that for the majority of children
with asthma it’s driven by allergy.”
According to the housing charity Shelter, England needs to build at
least 250,000 new homes each year. Yet could the rush to build be storing up
health problems for the future? On the rental side of the market, more than 20
per cent of UK households now rent privately and landlords are incentivised to
redecorate cheaply and fill their flats quickly. Many tenants experience what
could be called “Queen syndrome”: everywhere smells of fresh paint.
Paint is one of the biggest culprits in an unhealthy home. Walls,
ceilings and woodwork are covered with the stuff and home-makeover television
shows have normalised the idea of redecorating a room or two over a DIY
weekend. Yet, colour aside, how many of us give much thought to what we’re
splashing on to our walls (and our skin)?
Paint requires just three ingredients: a pigment (the colour), a solvent
(the bit that makes it a liquid), and a binder (which sticks the pigment to the
wall). How paint is made has changed little in the past century; what has
changed is the source of its components. “We have switched from naturally
occurring ingredients to derivatives of the petrochemical industry,” says
Edward Bulmer, an architectural historian and interior designer who sells his
own brand of environmentally friendly paint.
Bulmer’s Damascene moment came in the early 2000s when he was
commissioned to decorate a new part of Goodwood House, an estate in southern
England. “I was asked to be very careful about what I used in my work and judge
them by two criteria: their environmental impact and their toxicity,” he says.
“I was proposing stone and plaster and furniture made from wood, horsehair and
leather and curtains of wool. And then I met the paint and thought ‘what is
it?’ If you turn a tin of paint round, you can’t tell anything about what’s in
it, and if you don’t know the ingredients of something, you can’t judge it.”
Calls to major paint companies drew a blank; their technical departments
were unable — or unwilling — to offer a list of ingredients. Instead, they sent
data safety sheets. “They are a matter of compliance,” says Bulmer, “but they
only tell you about a small minority of the worst ingredients. They don’t tell
you about the main bulk of the paint.” So he decided to make his own.
Today, the average can of paint has an ingredient list as long as your
arm — much of it toxic or carcinogenic. And given that up to 60 per cent of
what goes on the wall then evaporates, if you don’t ventilate your home or
allow the paint to off-gas — that is, to allow toxic gases to be dispelled —
for long enough you are inhaling a large proportion of that.
Of course paint is not the only building material that can have a health
impact. MDF — medium density fibreboard — is a favoured material among builders
and carpenters looking to produce cupboards and shelving, and to box in pipes
or baths. It can give a very smooth finish and is cheap and easy to work with.
The downside is that it is made from extremely fine wood dust held together by
copious amounts of glue, which contains formaldehyde.
“It’s the asbestos of tomorrow,” says Gale. “We knew back in the early
1900s that asbestos was dangerous but it wasn’t banned until 1999.”
Formaldehyde can also be found in the backing of linoleum flooring, the glue in
plywood and other composite materials.
Heating systems, too, can cause health issues. Small, hot radiators not
only trap dust in and behind them, but create convection currents that disperse
that dust around the room. Underfloor heating is an improvement as the lower
temperature warms a room more evenly. Yet some heat is wasted (under sofas etc)
and it still creates convection currents. Gale suggests a similar radiant
system of pipes that can be fitted into a wall and plastered over, more evenly
warming a room without the strong convection currents that disperse dust.
So what can be done? Ventilation is key. The average family of four
produces 16 litres of moisture per week. The optimum relative humidity level is
50 to 55 per cent and to combat damp problems in poorly ventilated homes,
dehumidifiers such as Meaco’s Low Energy 20L can help regulate levels.
As the UK government is committed to an 80 per cent reduction in carbon
emissions by 2050, and new homes must have increased air-tightness to help meet
this target, a longer term solution would be to ensure that all new-builds are
fitted with more comprehensive ventilation systems.
The gold standard for Passivhaus and energy efficient buildings is
Mechanical Ventilation with Heat Recovery. An MVHR system brings in fresh air
from outside, using the heat from the stale outgoing air to warm it.
The pursuit of healthier building materials is starting to catch the
attention of larger organisations too. Google linked up with the Healthy
Building Network in the US last year to work on Portico, an online database of
materials that lists all ingredients and rates how healthy they are. The aim is
to enable designers, architects and developers to make informed decisions about
the buildings that many of us will end up living and working in.
Yet for homeowners looking to redecorate, Gale has his own basic
manifesto. “As a general rule,” he says, “the more natural the better.”
Architect: Gale & Snowden Architects Ltd. Photograph: The Modern House |
To find out more about Gale & Snowden and healthy buildings, please visit our website.
For more information on Building Biology please visit Building Biology Association.