Turn your home into a microclimate and save money
All buildings have an impact on the environment; they use 40 per cent of the world’s energy, emit 40 per cent of the world’s carbon footprint and use 20 per cent of the world’s available drinking water. The more buildings we erect, the less land is available, therefore it’s vital that when building we minimise our impact on the landscape. Making your home environmentally sustainable as well as energy- and water-efficient ought to be front of mind in any building or renovation project.
The aim is to live in a house that is cool in summer and warm in winter. Passive-designed buildings, which harness the climate to maintain a comfortable indoor temperature, reduce or eliminate the requirement for and reliance on mechanical heating or cooling, thereby reducing the amount of energy required (by some 40 per cent or more) by the average home.
Plants play a significant role in helping to control the temperature, which is why you should give as much consideration to the landscaping of your home as you do to the design and materials used in building it.
Houses that are designed and built using Environmentally Sustainable Design (ESD) principles are healthier and more desirable to live in, attract higher valuations and enjoy lower operating costs. One way you can create a healthier and more comfortable environment inside your home is to take advantage of nature to create a microclimate outside.
Creating a microclimate around our houses and buildings can significantly affect the temperature outside and inside throughout the year. Plants play a significant role in helping to control the temperature, which is why you need to give as much consideration to the landscaping of your home as you do to the design and materials used in building it.
A microclimate is the distinctive atmosphere of a small area that varies from its surrounding area. It could be a cave, woodland or forest area, a small courtyard or part of a garden. Examples of larger microclimates include valleys or mountains and large bodies of water. Microclimates of a less desirable type may exist where there are large areas of concrete, brick or other hard surfaces, which can absorb heat and reradiate this into the atmosphere. Tall buildings can also create microclimates where the temperature may be cooler owing to overshadowing and the creation of wind tunnels between structures. Buildings generally increase temperatures overall, however, with heat island effects due to the density/volume of buildings and number of roads, as in large modern cities.
Using microclimates to best effect
Your home as well as other buildings can benefit from microclimates, which can be created with appropriate landscaping. To produce a successful microclimate it’s important to first analyse your geographical location and individual site and consider the local temperature, amount and angle of sunlight, water, soil type and air circulation. It’s also important to consider what hard surfaces you will create outside, such as driveways, paths and entertaining areas. Paving and concrete act as thermal mass, collecting and radiating heat back into the atmosphere and your house, so an area of groundcover or lawn is a cooler option.
The time it takes to establish a microclimate around your home will vary from location to location and the size of the space to be used, so it’s important to plan this part of your home early in the construction phase. Of course, if you have an existing house, it will take longer as the plants will require time to become established. Landscape architects often plan their designs to take advantage of or to create microclimates, sometimes to planting species that may not usually be found in a particular area.
A strategically placed water feature can also assist with cooling as, when wind passes over the water, the air is cooled.
The western side of your house will be much hotter in summer and to protect this elevation you’ll want to consider hardy plants that can withstand the summer sun, including trees that give both height and volume. To allow some heat gain in colder months, deciduous plants are a good option as they drop their leaves in winter, allowing the sun’s warmth to penetrate, while providing a shady canopy in the summer. It’s also important not to shade your roof where you have PV and solar hot water systems installed. This will affect their performance as well as affect the north/west aspect of a building that’s working as a passive home.
A strategically placed water feature can also assist with cooling as, when wind passes over the water, the air is cooled. Water features also provide a delightful background both visually and acoustically. A water feature with the addition of plants will do an even better job as plants breathe, absorbing CO2; aquaponics plants also clean grey/polluted water.
Green roofs and green walls create microclimates, too. These areas act as insulation from heat entering the building or, in cold weather, heat inside from escaping. They also play a significant role in controlling air and noise pollution and provide additional habitats for local fauna. Further, green walls and roofs provide additional growing space for food, including herbs and vegetables for use in your kitchen.
If you live in an apartment, you can create a microclimate on your terrace or balcony. When doing this, it’s essential to ensure careful consideration of structural loadings. Growing plants on apartment balconies will provide much-needed shade, visual softness and contact with the environment. Growing herbs, vegetables and even fruit on a balcony also gives you access to fresh food and provides an environment to attract birds and insects, including bees, which are vital for pollination.
The impact of microclimates for comfort can be immense. Consider the hottest days in summer, when the inside of your house can feel like an oven, even with the windows open. Often the air temperature outside can be hotter than inside, so unless you have mechanical air-conditioning (which will require you to close up your home to work effectively), your home’s interior will be very uncomfortable and you’ll probably be better off closing the curtains or blinds — not necessarily the most comfortable way to live.
However, if your garden is landscaped appropriately, you can live inside your home in a much more pleasant temperature and with a healthier atmosphere and no need for energy-guzzling air-conditioning. This is the reverse in winter, where the inside of your home may be very cold and any heating inside can escape through large areas of glazing and poorly sealed doors or other draughty areas.
Providing insulation against the heat and cold is an essential element of building a home and can be enhanced with the use of appropriate planting, though this is really only effective in temperate climates or those where there’s no snow cover. Using plants inside buildings can have the same effect, plus they clean the air. For this application, however, you will need to give careful design consideration to plant selection and access to light and water systems.
Do you have large, evergreen trees or shrubs close to your house? They may prevent winter sun from helping to keep your home warmer in the cooler months, so it’s as important in winter as it is in summer to provide appropriate planting. Locate trees to the west and southwest, making sure not to overshadow your neighbours, thus robbing them of the sun during winter. This is one reason why large developments need to be designed correctly to include microclimates in the project’s overall design.
How to create your own microclimate
When creating a microclimate in your garden, consider the various areas you want to use. You may want to grow vegetables in one part of your garden — preferably in the north, northeast and northwest — and provide an entertainment zone in another. This will vary with site and climate. In yet another area, you may want somewhere for the children to play and even to install a swimming pool. Somewhere to hang out your washing should also be considered, as there’s nothing like the effects of fresh air on clean washing. All these areas will require different treatments, plantings, moisture, light and shade.
Walls, fences, water features, ponds, pools, patios and decks are all examples of microclimates. Where each one is placed will affect the conditions in your Garden. For example, if you have dry soil with lots of sun you could plant drought-tolerant plants, and if you have dry soil with shade, as under large trees, this will be a good spot for plants that would otherwise wilt in the sun. In an area with moist soil and lots of sun, you can plant anything that doesn’t mind wet feet, and for moist soil with shade you’ll want to use moisture-loving plants that won’t go mossy or mouldy. Of course, it’s possible to change the structure of your soil with organic matter, drainage and appropriate landscaping, depending on your desired use.
Green roofs and green walls create microclimates, too. These areas act as insulation from heat entering the building or, in cold weather, heat inside from escaping.
Microclimates also exist inside buildings. Consider that warm spot where the sun penetrates into the room in the middle of winter, or the cool, southern room where you can escape the summer sun; or a house with several levels, one of which is much cooler than the others due to the insulating factor of the floors above. Large glazed areas that capture the sun can double as drying rooms for clothes or food, and even be used to propagate plants for future sowing. It all depends on where you live and the climate in your region.
Climates are very complex and constantly changing and, with global climate change, our weather patterns are becoming increasingly unpredictable. Therefore, it’s important to analyse each location and take a holistic approach to your home’s design with an integrated system of both building and landscape; and, if possible, a total development.
On your marks …
Ready to create a microclimate around your home? Here are five easy ways to get started.
- Mulch your plants. Mulching is an easy way to control weeds, conserve moisture and protect your plants from the elements.
- Create hard surfaces. Driveways, pathways and paved areas made with dark material can absorb heat during the day and reradiate it inside at night, creating warmth in cooler temperatures. Alternatively, planting grass or ground cover will have the opposite effect.
- Protect on the west side. In the afternoon, the western side of your garden can be hot during the summer. Protect this area with tall trees and shrubs to help keep it cool. Plant deciduous trees to allow the sun to penetrate in winter.
- Build a wall. A wall has two sides: one in the sun and one in the shade (depending on where you build it). Take advantage of different temperatures and wind breaks to extend your range of plantings.
- Install a greenhouse. Grow your own plants and food and propagate next season’s crops protected from the external elements.
For more great garden ideas, why not check out our Wellbeing Directory
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