Energy efficient building materials

BANGLADESH is one of the fastest growing economies of the world. With population around ~156.6 million (march, 2013) and GDP ~496 Billion $(PPP, 2013), it is also one of the most densely populated countries, where Real Estate or housing sector is on its boom and businesses related to this sector are on its full swing. The contribution of real estate in Bangladesh's GDP is more than 7% (7.02% in 2009-10, REHAB), which is likely to grow in the coming years because of the higher pace of urbanization in the country. Ahead of providing physical shelter to people, housing significantly impacts the lives of the dwellers in terms of skill-development, income generation, increased security, health, self-confidence and human dignity. The Constitution of the People's Republic of Bangladesh too, recognizes shelter as one of the fundamental human rights. Distant from giving people their fundamental right, housing sector is also building the economy of Bangladesh by giving birth to a number of small to large scale industries, which in turn generate revenue and employment. Glass, ceramic, iron, steel, plastic and plumbing equipments are few of them. Having involved so many things consolidated with it, this sector becomes the most energy intensive sector of the country; both during and after establishment of the housing units. (Basically, this fact is true for almost every country of the world!). Deficiency of Energy is already considered as the biggest obstacle in the development of Bangladesh. So, it has become very crucial to save as much energy by any means possible in the housing sector, for the suitable growth of the country. Many ways are currently in use to save the energy used in housing sector. They include use of Renewable energy, use of more efficient systems etc, but the problem and challenge still remains. On house hold level, Renewable energy is very expensive to use. Besides, use of more efficient systems i.e. LED lights; highly efficient pumps etc, though technically successful, are still beyond the reach of many common people because of their high cost. So to meet the demands of common people with the need of the time of conserving energy, research scholars, engineers and architects have worked together to find the solution of this universal challenge and this consolidation has given rise to the concept of Green buildings, which are considered as the best measure to conserve and save the energy with lowest cost involved.

UPVC Windows: Not just the demand of market but Demand of time

To make use of green buildings in energy conservation more effective, the places of a building or house, where the energy is lost from, are to be understood. Below is shown the division of energy loss in a typical house. Windows stand only next to the walls in terms of energy loss; considering the fact that windows cover a very small area as compared to the walls. When we talk of the loss of energy through windows, we consider only the glass, not the frames. But frames are also a decisive part in saving this energy loss from windows.

Better fenestration technology is an integral part of green buildings and this fenestration technology includes both the glass and the frames with equal importance. The study and research on the loss of energy through frames and thus to conserve it by using better frame material, is relatively new in Bangladesh. So far, Aluminum, Timber and steel have been the main materials used in making the frames in the country but because of the global environmental concerns and better ecological and technical characteristics, UPVC is also emerging as a material to be used for the manufacturing of window profiles and frames, which in itself is a very fresh and innovative concept in Bangladesh.

Below is shown the comparison between all of these materials, considering various factors, what material is better to use for manufacturing these profiles:

Thus, we find that PVC is far better than aluminum and steel while using as window profiles' material of construction and marginally comparative with wood. But environmentalists, worldwide, discourage the use of wood and PVC itself becomes our best choice; this is where the demand of UPVC windows arises from. Looking very closely, there's this process of generating the demand of UPVC windows in Bangladesh, which finds its inception revolving around the infrastructural development and urbanization in the country.

Advantages of UPVC Windows in fenestration technology

Being an eco-friendly product, UPVC windows are not only good for the planet but also have a very good cost-benefit ratio. UPVC windows have enormous benefits and advantages. They can be summarized as follows:

1) Credible long lifecycle

• PVC profiles have been on the market for 59 years

• Modern, adjustable PVC formulation

• Salt resistant metal coating of hardware

• Maintenance free

2) Manufactured to suit every kind of home, versatile in style

• Carefully engineered to provide highest performance

• Easy operating hardware and efficient weather sealing

• Highest quality and aesthetics

• Can be fitted in all buildings

3) Requires low-maintenance

• Easy cleaning- only with water and mild detergent

• No preservative treatment and no painting required

• Oiling the hardware once in a year is recommended for proper functioning

4) Low impact on the environment

5) Best noise control characteristics among all materials used for frames

• Multiple chambers reduce sound between 33 and 45 dB.

6) Rain impact proof

• Profiles corners are fusion welded which does not let the outside rain comes inside the house at all.

• Profiles are reinforced to hold wind loads of all intensity.

• Uses gasket barriers for better functioning.

• Hydrolysis-resistant even to hot water and steam

7) Resistant to salt atmosphere

• PVC material contains 57% of rock salt which makes it 100% resistant to salt atmosphere

• Hardware used is made in electro-deposited zinc based coating using nanotechnology; thus hardware too becomes resistant to salt atmosphere.

• TPE and EPDM gaskets

• Internally Protected steel reinforcements

• No aluminum oxidation

8) Cyclone resistant: PVC window systems are also able to work successfully even in typhoons. Some examples of such products manufacturer are-

• LG Korea for winds speeds up to 7000 Pa (~380 km/h)

• Fenesta Series-3000 in India for 3000 Pa (~250 km/h)

9) Flood Proof: PVC windows are also able to work efficiently in case of floods. The areas which are prone to floods must use UPVC windows in their fenestration.

10) Intact and super functional even in very cold environment

• Works good even if outside temperature reaches up to -30°C

• Super functional if the outside temperature continuously remains up to -15°C.

11) Highly smog resistant: UPVC windows have very good resistance against smog and also they are able to withstand an extremely polluted environment. Besides, when PVC is recycled, chlorine gas and hydrochloric acid are not released into the atmosphere.

12) Fire Resistant

• Slow to ignite

• Slow flame spread

• Halogen Chlorine's presence makes it Self-extinguishing

• If burns, Hydrogen chloride can serve as a warning to evacuate, as CO is colorless, providing no warning of its presence

13) Good chemical features

• Good chemical resistance.

• Food compliant.

• Chemically stable and does not de-polymerize.

14) UV-radiation resistant

• Anti-oxidants stabilize PVC against degradation

• UV-stabilizers protect PVC against sunlight

• No problem with temperatures up to 60°C.

15) Eco-friendly and Insect free

• Cut down carbon dioxide emissions

• Once chlorine is processed into PVC, it is chemically locked

• PVC is 100% recyclable, which keeps it out of the landfills

• PVC stabilizers used are non-toxic and do not affect human health or the environment

• PVC has been specified as an alternative to wood which helps to slow down the rate of cutting down forests.

• PVC is also resistant to termites, carpenter ants and mosquitoes

16) Safe and Secure: PVC windows are also highly safe and secure which comes with security hinges and hinge guards and lockable handles.

17) Very good cost-benefit ratio

• No future maintenance cost

• PVC windows are highly energy efficient

• Cut down energy consumption for heating and air conditioning

• As demand for PVC windows is increasing worldwide, it makes it a good sales product.

With all these facts, Federal laboratories- The Commonwealth Scientific and Industrial Research Organization and The Swiss Federal Laboratories for Material Testing and Research concluded that "there is no alternative material to PVC in its major product applications that has less overall effect on the environment".

POTENTIOAL MARKET OF UPVC WINDOWS IN BANGLADESH

In Bangladesh, the requirement of UPVC windows is not merely driven by marketing policies, but the topography and demography of the country make the use of UPVC windows a necessity in Bangladesh. The characteristics of Bangladesh's Geography, housing sector and its Demography which have the potential to drive the growth of UPVC window market in country. On the other hand construction, urbanization and the size of the real estate sector are increasing, the growth of PVC window market is also going to welcome an overwhelming response and growth in the coming years in the country. With so much happening in the real estate as well as in industrial sector in Bangladesh,

Leading UPVC Window manufacturing companies in Bangladesh.

World Glazing

Winpen Ltd.

RFL Plastics Ltd.

............................................................................

Ar. Md. Nafizur Rahman, Architect & Researcher

nafizhbri@gmail.com