Green building is not a new fashion stream in design and architecture. Green building is a possibility to create harmless, energy efficient and environmentally friendly buildings. In the 1970s energy crises and environmental pollution affected on the progress of sustainable buildings. The price for sustainable products and materials fall, green buildings are becoming good for the environment, tenants and occupiers. Conventional building consumes too much natural sources, like energy, water, woods etc. while green building uses renewable resources as sunlight, plants, rainwater. Green building is a LEED-certified (Leadership in Energy and Environmental Design) building. One of the most important components of green building are energy and water efficient technologies which are generally not available in regular buildings. Although green building is more effective and good for bottom line, when creating it construction employers and designers should take into consideration some disadvantages too.
Advantages of Green Building:
Very often green building is considered to be expensive as usually all kind of modern building methods. However it saves much more money from the moment of creating during its lifetime as ordinary buildings. It works with any kind of green structures – office buildings, schools, churches, factories and others type of buildings. Designing and building green structures cost approximately the same as regular buildings. Even if they are higher in cost a little bit, because of some special requirements, during their usage they save so much energy that the money spent on its creation will return at least 10 times. The Californian Sustainable Building Task Force carried out a study in 2003. According to this study even 20% of investment into green building will elaborate 10 times more saving. So there is no significant difference in prices. A green building can be expensive as much as a conventional building.
• Energy efficiency
Green building has a great advantage of reducing both embodied and operating energy consumption. Studies proved that those buildings which are built with wood will have a lower embodied energy than buildings made of brick, steel or other materials. What about operating energy? Designers try to find solutions to reduce it too. They use extra-insulation, high-performance windows, and passive solar design. The latter is very efficient especially if the windows are effectively placed. Also other ways of renewable energy are used too. Wind power and hydro power can also notably reduce the influence on environment.
• Water efficiency
Water consumption is another objective in sustainable building. Water can be wasted by drip irrigation, leaking (toilet leaking can waste up to 90 gallons per day), pool showers. Recycling rainwater and using it for toilet flushing can save waste-water. Water saving shower heads, ultra-low flush toilets and other conserving fixtures can minimize waste-water.
• Material efficiency
Green buildings are built from green, rapidly renewable, non-toxic, reusable and recyclable materials as lumber, bamboo, straw, recycled metal/stone, sheep wool, compressed earth block, concrete, cork etc.
• Temperature Regulation
Urban heat islands are elevated temperatures mostly in urban areas, formed mostly on surfaces where permeable and moist became impermeable and dry due to some buildings, roads etc. Urban heat island effect is caused mostly by the heat holding properties of tall buildings and urban (often toxic) materials – asphalt, concrete. It can be compensated by more green areas around the buildings such as green roofs and rain gardens.
• Indoor air quality
When constructing green buildings great emphases are put on the ventilation system. It can be powered in different ways – passively, naturally or mechanically. It doesn’t matter in which it is powered, the most important thing that a building should have a properly designed ventilation system in order to have a filtered andcleanerair. During construction low or zero emission materials are used. Most materials used for ordinary buildings are toxic, some of them radiate gases or include volatile organic compounds. It has a bad influence on occupant’s health and productivity. According to the data of the US Environmental Protection Agency indoor air pollution can be 2-5 times worse than outdoor air quality. It can cause early asthma and other respiratory disease. It is provoked by radon gas that’s found in conventional buildings. Another considerable feature of air quality is the control of dampness. If ventilation from bathrooms, kitchen and other isolated rooms is bad, it can lead to mold growth, dust mites or to the emergence of other bacteria. To avoid this problem effective ventilation system is not always enough; well-insulated building envelop is also needed.
• Indoor environment quality
Except poor air quality other circumstances like poor lightening, temperature variances, furniture, carpeting, pesticides, paints and high concentration of pollutants are causing different diseases – headaches, dermatological problems, allergies etc. The environmentally friendly circumstances of green building create healthier atmosphere.
Green buildings need less maintenance. For example most green buildings don’t require exterior painting so often. Also as far as natural sources were used during its construction, they are not destroyed so quickly.
• Improved Employee Attendance and Productivity
Natural lightening, good ventilation, healthy circumstances all influence the health of green structures’ occupants. People are becoming less sick, they are more productive and their impact on work is more high and effective. A study made in Seattle among 31 green buildings showed that in LEED-certified buildings the absence of employee was decreased into 40 percent. Another research showed 30 percent less sick days plus a 10 percent growth income per employee. This way green office is more attractive and retaining for employees.
• Higher Property Value
Green buildings have low energy cost. Their use of gas, water, energy is highly reduced. A building can keep a high sale value if it contains sustainable components.
A green building can be easily tuned into a net zero building. A net zero building or zero energy home is an active house. Instead of spending money on it, you can earn money with it. These buildings have almost zero consumption. Moreover they can create more energy than they need, they can supply energy(electricity) back into the electrical grid.
• Tax benefits
Tax provisions are initiated to improve energy efficient green buildings.It is supported on local, state and federal level. In the Economic Stimulus Act of 2008, PL 110-185 (ESA), the Housing Assistance Tax Act of 2008, PL 110-289 (HATA), the Emergency Economic Stabilization Act of 2008, PL 110-343 (EESA), and the American Recovery and Reinvestment Act of 2009, PL 111-5 (ARRA) you can find what kind of estate they are included.
• Improved Retail Sales
A survey in the state of California proved that if stores are lighted with skylights/natural light, the personage of sale is increased into 40%. The conclusion is that retailers using daylight can reduce their electrical costs.
Disadvantages of Green building:
• Air-cooling features
Particular cooling components that control precisely the indoor temperature in green buildings don’t exist. The only thing that influences it is natural ventilation, which cannot be regulated.
To amend sun exposure, green building may need a correct structural orientation. It influences how natural light enters the building, how to shade some part of it. As far as the building will contain recycled resources the location of the building is affected by the land’s humidity, the circumstance of the surrounding area.
• Availability of materials
In urban areas materials can be found easily than in rural areas. Green buildings require special materials. A lot of eco-friendly materials re not available in the US, so sometimes these materials are hard to find and transportation fees may be high. If you order them from the internet you should pay additional cost for shipping and handling.
To build a green building in some cases takes more time than an ordinary one. Sometimes it takes too much time to find the needed material.The client can delay the construction.
• Green roofs
Green roofs consist of several layers plus a vegetation layer, culture medium, drainage, isolation, waterproofing membrane, and roof support. Green roofs are heavier than simple once, so the roof’s strength should be improved in order to construct this type of roof correctly.
Many believe that the cost of green building is cost-prohibitive. You need to invest a lot of money. However later with energy saving possibilities the invested money may come back.
• Low indoor quality
Green buildings are eco-friendly and healthy, but too much emphases are put on sealing them. This isolation may cause indoor pollution. It can be harmful to the health of the occupants. Damage to health can also cause fluorescent lights. Their radiation in isolated places can lead to health problems.
As we can see all the advantages and disadvantages are environmental, economic and social. They are influenced mostly by its cost, energy efficiency and influence to our health. Although the advantages of green building are impressive, there are still some restrictions. For this reason designers and project managers should look through all the requirements for green building. Almost for all the disadvantages of it we can find a solution. In order to achieve a good result don’t forget to consult a professionally qualified team.