LANDSCAPING FOR ENVIRONMENTAL PURPOSES
Energy saving is possible with landscaping.
Although it is not possible to control temperature ,wind and other natural elements certain landscape particles can help modify the climate in and around the home.
By placing trees,shrubs,vines and landscape structures properly home owner reduce the energy required to keep homes comfortable during winter and summer.Along with the reduction of energy bills,a well planned landscape adds beauty,interest and increased property values.
LANDSCAPE AND LANDSCAPING
Landscape means everything that surrounds us where we are.
Landcsaping means a collective activities,features and accessories that turn a part of the landscape into a pleasant outdoor place.
Landscaping is a good sense of planting with choice of plants varying according to the local landscape
Landscaping is mixing and merging colures to create a mood resonance with interiors,
Landscaping bring out the beauty of the structure,as well as disguise the existing flaws.
3. LANSCAPING FOR ENERGY EFFICIENCY
A well designated landscape will
Cust summer and winter energy costs dramatically.
Protect the home from winter wind and summer sun.
Reduce consumption of water ,pesticides and fuel for landscaping and lawn maintenance.
Help control noise and air pollution
4.HOW ENERGY CONSERVATION IS DONE
1. HEAT EXCHANGE AIR INFILTRATION
2. SOLAR RADIATION
3. PROVIDING SHADE
4. WIND PROTECTION
5. PASSIVE SOLAR COOLING
PASSIVE SOLAR TECHNIQUES
Heat exchange in a home occurs through three major processes ; air infiltration , heat conduction and transmission of radiant energy through windows
The first heat exchange process in air infiltration is the passage of outside air through cracks around windows and doors or other openings in house walls or openings.
One way outside air is forced through these openings by pressure difference caused by wind on the outside of the home
The second heat exchange process in conduction through materials from which the home is built.
The amount of heat conduction depends upon the insulating property of the building materials,thickness of materials,surface area available for heat flow,and the temperature
Differences between the inner and outer surface of walls and ceilings,and thus reduce heat conduction.
The third process of heat exchange in home is transmission of solar radiation through windows.
Large expanse of east or west facing glass admit undesirable solar radiation in summer. Large expanse of south facing glass help home in winter.
Vegetation around the home can regulate solar radiation during different seasons of the year.
Proper house design and landscaping can reduce or eliminate the need for air conditioning.
The way to provide shade is to plant deciduous trees in arc encompassing the home on the east, southeast, south , southwest and west sides.
Trees that do not overhanging the roof will not cast much shade on it at the midday due to the high position of the sun in the sky. These plant shade trees as close to home as practical.
The arrangement that provide shade in summer may be detrimental in winter if they block solar heating .
However the winter sun is typically less than 45 degree above the horizon. So shading will be larger from tree trunks.
For this reason plant only those trees needed for summer shade along the southern edge of the home.
The other important climatic element to be controlled by landscaping is the wind.
Research conducted on the great plains has shown that up to 25% energy saving for heating is possible from wind break.
As evergreen, properly placed can divert cold wind away from the home.
However a wind break can provide reasonable protection at a distance of six times tree height.
PASSIVE SOLAR COOLING
Unlike active cooling systems that require panels and other expensive apparatus.
passive cooling system pivots on the bulding orientation towards the sun and position of its windows.
These concept also extend into the landscape where plants have a great deal of influences on comfort levels of indoors.
PASSIVE SOLAR TECHNIQUES
Passive solar heating techniques generally falls into one of three categories:direct gain, indirect gain and isolated gain.
Direct gain: direct gain is solar radiation that directly penetrates and is stored in living spaces.
Indirect gain: indirect gain collects, stores and distributes solar radiations using some the thermal storage materials through conduction, radiation or convection then transfers energy indoors.
Isolated gain: Isolated gain system collects solar radiation in a area that can be selectively closed off or opened to the rest of house
The buildings southern exposure must be clear of large obstacles(eg:tall buildings, tall trees) that blocks the sunlight.
Although a true southern exposure is optimal to maximize solar contribution, it is neither mandatory nor always possible.
Provided the buildings faces within 30 of due south-facing glass to balance heat again.
Heating with solar energy is easy: just let the sunshine in through the windows.
The natural properties of glass let sunlight through but trap long-wave heat radiation, keeping the warm (green house).
The challenge often is to properly size the south-facing glass to balance heat gain and heat properties with out over heating
LANDSCAPING SAVES MONEY YEAR-ROUND
Summer:-Shading and evaporation from trees can reduce surrounding air temperature. Studies have shown that a well planned landscape can reduce an unshaded homeâ„¢s summer air conditioning costs by 15% to 50%.
Winter:- Trees ,fences or geographical features can be used as wind breaks to shield your house from the wind. Houses with wind breaks placed only on windward side averaged 25% fuel consumption than similar but unprotected homes
DESIGNING LANDSCAPE AROUND YOUR HOME
Plant trees on the east, south, and west sides of your home. Shade walls and windows from the summer sun.
Plant trees, shrubs and ground cover to shade the ground home and reduce heat reflected to your walls and windows.
Use short shade trees to block reflected heat while admitting the sun.
Sketch your house and site. Allow Ã‚Â¼ inch for each foot. Identify north, south, east and wet. Mark doors, windows and other glass areas. Measure the height of house.
Next observe how the sun and wind affect the site. Observe the wind during the storm.
Observe the sun at different seasons. Note how it strikes the house between 9 am and 3 pm in the winter.
Determine how the sun strikes the house during the summer, particularly in the early morning and late afternoon.
Add shade trees to maximize summer shading and solar heating.
User fences, wind break planting and shack trees to provide a sun pocket on south side of your home where outside activities can take place during our sunny, cool but comfortable winter days.
BENEFITS OF LANDSCAPING
Trees and bushes can block much of the sunâ„¢s heat before it strikes your windows and walls.
Shade trees can significally reduce surrounding air temperature.
Trees, shrubs and ground cover can reduce the heat related from the ground to your walls and windows.
Deciduous trees lose their leaves in winter, taking them ideal to block the sun in summer while allowing the sun to warm your home in the winter.
DRAWBACKS OF LANDSCAPING
Lack of importance given to it.
Lack of products and technically aware people to implement them.
Need for adequate quality and quantity of soil to allow plants to grow to mature size.
Drip irrigation systems are needed for dry periods.
Constant maintenance is required in which very few architects have an active interest.
Landscape is not merely an add or an decorative features ,to be incorporated in to a project at its conclusion.
It should be a part of the initial planning itself, so that it does not overshadow the architectural project.
Instead it should enhance it, blend with the structure and complement it.
Plants not only control erosion and beautify the landscape, but they also make homes more comfortable and save energy .
A well planned landscape is one of the best investments a homeowner can make.