How can a home help protect our health during the colder months?
As we move into the colder months of the year, a general increase in illnesses and health problems are more noticeable in comparison with the warmer summer months. It’s worth taking a moment to look at how our immediate built environment can have adverse or positive impacts on our health, particularly during colder periods with fewer daylight hours.
This blog piece is intended to give an overview of the general construction and design principles of homes that influence our health, to explore in more detail, which include:
· Daylight and appropriate artificial lighting;
· indoor air quality;
· thermal comfort;
· humidity and moisture control;
· connection to nature;
· sense of place and community, and
· accessibility.
Daylight and appropriate artificial lighting
Reduced daylight hours in winter are attributed to increased health problems – lowered vitamin D levels give greater susceptibility to illness, and the effect on our circadian rhythms can contribute to Seasonal Affective Disorder (SAD), or other mental health issues.
We recently had a daylighting assessment undertaken for our sunken cohousing new build project to ensure all the primary living spaces have a suitable daylight factor (percentage of daylight that reaches inside the building with an overcast sky).
The effects of artificial lighting on health are also well documented – the level of illumination, colour temperature, flicker rate, colour rendering index, and positioning all need to be considered.
Daylight analysis by consulting engineers
Thermal comfort
The next obvious influence on health is temperature, being too cold for extended periods of time can deteriorate our immunity and wellbeing.
We try to design our new build houses to, or close to, Passivhaus standards, which are highly thermally efficient and include technology such as Mechanical Ventilation with Heat recovery (MVHR) that helps eliminate as much heat loss as possible. This keeps the house thermally comfortable whilst saving money on energy bills.
Overheating can also be an important health issue, as we wrote about in a recent blog.
Indoor air quality
Material off-gassing - VOC’s, particulates, formaldehyde etc have all been linked to cancer and other health conditions. These are mostly produced by man-made or highly processed materials, such as man-made insulations, adhesives, MDF, carpets, furniture, and certain paints. Natural construction materials and insulation are much safer (although timber does naturally off-gas formaldehyde, it does so for a much shorter period than other materials).
Ensuring an adequate ventilation rate helps control indoor air quality, mechanical ventilation can be linked to CO2 sensors, for example (not because slightly higher levels of CO2 are harmful to health, but it works well as an indicator for raised levels of pollutants). Certain plants can help absorb these toxic gasses to.
Using natural finishes and materials helps minimise off-gassing of toxic gasses.
Humidity and moisture control
Effective ventilation is an important part of controlling moisture in buildings, however, a report from the UK Centre for Moisture in Buildings suggests that ventilation alone is not an effective strategy for moisture control – optimising the order of construction build-ups to prevent interstitial condensation, especially in retrofits, and using breathable and/or hygroscopic materials that are able to release and modulate the moisture content in the air is also an important consideration. Natural materials will always be best at doing this.
Some of our new buildings that are due to be going on site soon have an internal lining of Hempcrete block, which is highly effective hygroscopic material, and will help control the relative humidity both in the internal space and within the wall itself. They also add thermal mass to the building which will help regulate the temperature.
Our previous blog posts ‘Airtightness & Breathability’ and ‘Airtightness in detail’ explore this further.
Connection to Nature
Access and connection to green spaces has a huge influence on our wellbeing, and we’ve written before about the Importance of integrated landscape design and redefining our relationship with nature.
The connection between inside and outside is also a part of this, where how we move and look between the two has a strong influence on a building’s connection with its context, which could be as simple as having a kitchen sink that has a looks out of a window to a good view.
Access to green and blue infrastructure has proven health benefits.
Sense of Place and Community
It’s hugely important for our mental wellbeing to feel connected to the world we live in, and our immediate environment – creating homes that have a clear ‘heart’ that make them enjoyable places to live is a big part of what we do.
Our recent co-housing project is based on a model that has shared garden spaces and workspace. Other forms of co-housing share more or less spaces, including kitchens, dining areas, living areas and common houses - sharing these resources for mutual benefit, and creating a supportive community for everyday worries or times of crisis.
Shared garden spaces in a co-housing scheme
Accessibility
Making a house accessible to its inhabitants is important – often we are asked to design homes to be future-proof, so adjustments can easily be made to accommodate the future needs of occupants – for example having a place where a lift can easily be installed, or a room that could easily be converted to a bedroom on the ground floor with level access.
How accessible each part of a building is for cleaning and maintenance can have surprising health impacts – rooflights that can’t be cleaned will reducing indoor daylight levels over time, areas that collect dust will attract mites and spread through the house, if the entire kitchen floor has to be taken up to fix a blocked pipe it will cause unnecessary disruption and mental stress.
We’ll look to explore some of these topics in more detail in future blog posts.
Written by Julian Woods