For the last couple of years, it seems like barely a week has gone by without an alarming sign of climate change. There have been extreme weather events, unexpected wintry conditions in California, and the record-breaking heatwave we saw here in the United Kingdom last summer. The government has made pledges that it will take the issue seriously, but there has been a lot of scepticism from leading figures about how much that will actually amount to. Businesses and individuals must also step up and take responsibility.
When it comes to construction, there are a lot of different areas that require focus. So much of the conversation around the construction and property industries over the last couple of years has focused on other issues which, while admittedly important, do not factor in the long-term environmental concerns. For example, there was a huge amount written about the shortages in construction supplies and the shortage of skilled workers in that industry. Meanwhile, the property market ballooned during the pandemic years and has since come crashing back to earth. As we look forward to the rest of the year and the years beyond, here are the major environmental issues that construction firms must address when working.
1. Air Pollution
Air pollution has been pushed to the forefront in recent months. For example, London’s mayor Sadiq Khan has made cleaner air a considerable part of his mission. It is important to remember that during the construction process, there are a lot of opportunities for exhaust fumes and other noxious vapours to be emitted for extended periods.
Construction firms must be aware of the air pollution they are causing and look for ways to mitigate it or rule it out entirely. A simple example of how they can cut down on exhaust created is by using electric vans and other vehicles to transport materials to the work site.
2. Non-Recycled And Non-Recyclable Materials
This is an area that every business needs to focus on, regardless of sector, but it can be particularly relevant here. People looking to build their properties from scratch may insist on using entirely new materials, but there is no need for such a definitive approach. Take something as simple as a wooden deck, for example. Recycled materials are just as hardy, just as effective, and just as easy to style.
It is the contractors' responsibility to offer a range of materials to their clients and recommend using recycled materials where they can. This will massively cut down on the amount of waste that the construction industry generates. It is also important to think about using recyclable materials.
So much waste from construction projects ends up in landfills. It is vital that the industry considers this issue and tries to avoid using everything from single-use plastics to non-biodegradable materials.
3. Impact On The Local Wildlife
The local wildlife will be affected every time a construction project gets underway. There is such a massive number of different elements and species at play that the idea that a project could be completely free of this issue is a hard one to believe. However, with the right preparation, surveys and consideration, the impact can be minimal. The specifics will vary from project to project depending on the location and the type of wildlife in the area. For example, a project near water must consider everything from fish and frogs to the animals that use the space.
One of the most important species that anyone considering renovating or demolishing a building must think is bats. Bats are a protected species in the UK, and they often make their nests in roofs, lofts, and barns. They are also often found in trees, and a bat survey must be conducted to ensure you are not damaging their habitat.
The first step is to take a preliminary roost assessment. If a roost is found, you will need further surveys about the best way forward. For more information about bat surveys and other wildlife surveys, talk to the team at Arbtech. They can help you to get surveys done quickly and efficiently and advise on how your project can proceed.
4. Noise Pollution
This point may seem a little less grave than some of the others discussed already, but it is a major factor to the local people and wildlife. Sustained noise pollution can be a serious problem, so it is advised that construction companies check with the local council before they begin a project. Work must be restricted to certain times of day, or it may be that the project needs to be moved entirely.
5. Using Methods That Cause Erosion And Contamination
As unfortunate as it may be, there are still many ways that construction companies can damage the local environment through carelessness. For example, it is possible for the soil surrounding the worksite to become eroded thanks to the coming and going of heavy vehicles and heavy equipment, not to mention the ongoing disruption of the construction work itself. Soil and water contamination is also a significant risk on many projects and requires constant vigilance from the people working on the site to ensure that it is not happening.
One of the main factors contributing to these harmful scenarios is businesses not investing in newer techniques and new equipment, which are less likely to have a negative impact. Given the challenging market, it is understandable that spending a lot of money is the last thing any firm wants to commit to. However, the environmental impact of any construction project must be kept to a minimum.
Sunday, May 16, 2021
The Bhand Deval Jain temple is built in the north of the eleventh century. The temple is in the Mahakoshal area of Arang. The temple is built in Bhumija architecture. The bottom of this temple has detailed ornaments. It has a sole that supports a pedestal on the wall and two rows of statues. The temple layout plan is a star-shaped one known as the stalette. The temple grows up to five floors, considered an unusual feature. The temple's face is on the west side. The temple is in harsh condition. In the past, a pavilion and a porch probably existed as part of the temple. The damaged front of the temple tower has been plastered without any decoration and also white. The northeast and southeast faces of the Temple Tower, all that were diluted, have been repainted in brick and mortar, but seriously. However, the overall view of the tower is still pleasant. Once upon a time, this temple was used as a survey marking station. As there was a tendency for the upper half of the tower to structurally explode by its borders, a metal strap bracing has been wounded around the tower in the middle section to give it stability. The top of the tower has a similar strap wound round. A large number of paintings have been engraved on the exterior and interior faces of the temple. The bigger images are engraved in two lines. Above the lines of bigger images, a line of carving small images is drawn. Inscription panels, flowers, and a line of highly decorated depictions of a royal march of horses, animals and people based on large images. The exterior faces of the temple are decorated with carved paintings.
A 500 metre road from Ratmalana to Borupana, South of Colombo had been paved with an asphalt mixture containing shredded and molten plastic extracted from municipal waste.
Non-recyclable plastic waste is taken from municipal waste (in Sri Lanka plastic, paper and food waste is now separated in households) shredded and heated with aggregates at 165 degrees centigrade.
"The molten waste-plastic-mix coats the heated aggregates before being coated with bitumen," the firm said.
"The new material – waste plastic modified asphalt concrete mix – will be applied for surfacing of roads under 150 degrees centigrate temperature. "
The plastic asphalt mixture not only solves the waste problem but cuts road construction costs and makes the pavements more durable.
Tests are conducted on the pilot project, the company said.
"Similar waste plastic modified asphalt mixes are successfully applied to road surfacing in countries such as UK, Canada, Netherlands, Philippines, India and Indonesia,"
The Plastic and Bitumen Mixture
Using recycled plastic for road building sounds simple, but it actually requires a complex process to create the right material. "Different plastics do different things to bitumen," he explains. "If you use the wrong mix, it actually can make the bitumen more brittle."
It is good to avoids using PET bottles and other types of plastic that are easily recycled, and instead concentrates on types of waste plastic that might otherwise end up buried in the ground. Reid declined to go into too much detail, so as not to reveal too much about MacRebur's proprietary process.
In addition to keeping plastic out of landfills, the company's plastic road materials can save about 1 ton (.907 metric tons) in carbon dioxide output for each ton of bitumen that the plastic replaces, according to this fact sheet from MacRebur's website.
சேகரிக்கப்பட்ட பிளாஸ்டிக் கழிவுகள், 1.60 மி.மீ. முதல் 2.50 மி.மீ. அளவுள்ள சிறு சிறு துகள்களாக வெட்டு இயந்திரங்களின் உதவியால் வெட்டப்பட்டு, சேகரித்து வைக்கப்படுகிறது. பின்பு இவை, தார்ச்சாலை அமைக்க சேகரிக்கப்பட்ட 110° செல்சியஸ் அளவிற்கு சூடுபடுத்தப்பட்ட கற்களுடன் சேர்த்து சுழற்சி முறையில் கலக்கப்படுகிறது. அவ்வாறு கலக்கப்படும் போது, கற்களில் உள்ள 1709 செல்சியஸ் வெப்பத்தினால், 30லிருந்து 60 வினாடிகளுக்குள் சிறு துகள்களாக நறுக்கப்பட்ட, பிளாஸ்டிக் துகள்கள் இளகி, கற்களின் மேல் போர்த்தியது போல், கற்களின் மேற்பரப்புகளை முழுவதுமாக மூடிவிடுகிறது.
இவ்வாறு இளகிய பிளாஸ்டிக் கழிவுகளுடன் சேர்க்கப்பட்ட கற்கள், உறுதியானவையாகவும், பிடிப்புத் தன்மையுள்ளதாகவும், மாறிவிடுகிறது. மேலும், கற்களின் மேற்பரப்பில் உள்ள சிறு சிறு நுண் இடைவெளி முழுவதுமாக மூடப்படுவதால், அதனுள், மழைநீர் அல்லது உப்பு கலந்த நீர் புகாமல் தடுக்கப்படுகிறது. இதனால், கற்கள் மழைநீரை உறிஞ்சி சிறு சிறு கற்களாக உடைவது தவிர்க்கப்படுவதுடன், சாலை குறுகிய காலத்திற்குள் பாழ்படுவது தவிர்க்கப்படுகிறது. இவ்வாறு, இளகிய பிளாஸ்டிக் கழிவுகளுடன் சேர்க்கப்பட்ட கற்களுடன், 1650 செல்சியஸ் வெப்ப அளவில் சூடுபடுத்தப்பட்ட தார் சேர்க்கப்படுகிறது.
மேலே கூறப்பட்ட வெப்ப அளவுகளில், தயார் செய்யப்பட்ட கலவையானது, 1109 - 1209 செல்சியஸ் வெப்ப அளவிற்குள்ளாக, தயார் நிலையில் உள்ள சாலைகளில் பரப்பப்பட்டு, கனமுள்ள சாலை உருளை வண்டி மூலம் இறுக்கம் கொடுக்கப்பட்டு, பிளாஸ்டிக் தார்ச் சாலை அமைக்கப்படுகிறது. 10 சதுர மீட்டர் அளவும் 25 மி.மீட்டர் கனமும் உள்ள பிளாஸ்டிக் தார்ச்சாலை அமைக்க, 27 கிலோ தார்க்கலவையும் 3 கிலோ பிளாஸ்டிக் நறுக்குகளும் தேவைப்படும். சாதாரண தார்ச் சாலை அமைக்க 30 கிலோ தார்க்கலவை தேவைப்படும். ஒரு பிளாஸ்டிக் சாலை அமைக்க தார்க்கலவையின் அளவில் 10 சதவீதம் பிளாஸ்டிக் நறுக்குகள் தேவைப்படும். இவ்வாறு அமைக்கப்பட்ட சாலைகள், உறுதி வாய்ந்தவையாகவும் மழைக்காலங்களில் சேதமடையாமலும் பிளாஸ்டிக் கழிவுகளின் பயன்பாட்டினால் புற ஊதா நிறக் கதிர் வெளிப்பாடு இல்லாமலும், அதிக கனரக வாகனப் போக்குவரத்தை தாங்கக் கூடியவையாகவும், குறைந்தது 7 வருடங்களுக்கு எந்தவித சேதாரம் இல்லாமலும் பயன்பாட்டில் இருக்கும்.
Alternative Method
தற்போது பல்கலைகழகங்களில், கழிவு பிளாஸ்டிக் பொருட்களைக்கொண்டு வீதி அமைத்தல் எனும் விடயத்தின் கீழ் (Using Waste Plastic in Road Construction) எனும் தலைப்பின் கீழ் பல ஆய்வுக்கட்டுரைகள் வெளி வந்துள்ளன. இதில் பாவிக்கப்படும் தாருக்கு சிபாரிசு செய்யப்பட்டளவு பிளாஸ்டிக் சேர்க்கப்பட்டு தார் வீதிகளுக்கு பாவிக்கலாம் என கூறப்பட்டுள்ளது. இதனடிப்படையிலேயே எனிவரும் காலங்களில் கார்பட் வீதிகளுக்கு போடப்படும் அஸ்போல்ட் கொங்கிறீட்டுடன் சிபாரிசு செய்யப்பட்ட அளவு பிளாஸ்டிக் சேர்க்கப்பட்டு கார்பட் வீதிகள் அமைக்கப்படவுள்ளது.
இவ்வாறு பிளாஸ்டிக் சேர்ப்பதனால் வீதியின் பாவனைக்காலம் கூடுதலாகவும் வீதிகள் உறுதியாகவும் இருக்கும் எனவும் கூறப்படுகின்றது அத்துடன் மிக முக்கியமான விடயம் நகரிலே சேகரிக்கப்படும் பிளாஸ்டிக் போத்தல்கள் மீள் பாவனைக்கு உட்படுத்தி சுற்றுச்சூழலை பாதுகாக்கவும் முடியும்.
திருகோணமலை நகராட்சிமன்றம் பரீட்சாத்தமாக இராஜவரோதயம் சதுக்கத்திலுள்ள சிறிய வீதியொன்றிற்கு துண்டுகளாக வெட்டப்பட்ட பிளாஸ்டிக் போத்தல்களை தாருடன் உருக்கி 12.03.2021 அன்று வீதி தாரிடும் வேலையை ஆரம்பித்தது. தாரினையும் பிளாஸ்டிக்கினையும் உருக்கிய கலவையைக்கொண்டு சிறப்பாக வீதியை அமைத்துக்கொண்டது.
The selection of green building materials and products represents a critical strategy in designing a green building. Green building materials offer specific benefits to the building owner and building occupants and are as follows:
Reduced maintenance/replacement costs over the life of the building.
Energy conservation.
Improved occupant health and productivity.
Lower costs associated with changing space configurations.
Greater design flexibility.
Building and construction activities worldwide consume 3 billion tons of raw materials yearly, or 40 per cent of total global use. Using green building materials and products promotes the international conservation of dwindling nonrenewable resources.
In addition, integrating green building materials into building projects can help reduce the environmental impacts associated with the extraction, transport, processing, fabrication, installation, reuse, recycling and disposal of these building industry source materials.
Selection criteria for green material
A) Resource efficiency:
Recycled Content: Products with identifiable recycled content, including post-industrial content, with a preference for post-consumer content.
Natural and renewable: Materials harvested from sustainably managed sources preferably have an independent certification (e. g., certified wood) and are certified by an independent third party.
Resource-efficient manufacturing process: Products manufactured with resource-efficient processes include reducing energy consumption, minimizing waste (recycled, recyclable and or source-reduced product packaging), and reducing greenhouse gases.
Locally available: Building materials, components, and systems found locally or regionally save energy and resources in transportation to the project site.
Salvaged, refurbished, or remanufactured: Includes saving material from disposal and renovating, repairing, restoring, or generally improving the appearance, performance, quality, functionality, or value of a product.
6) Reusable or recyclable: Select materials that can be easily dismantled, reused, or recycled at the end of their useful life.
7) Durable: Materials that are longer lasting or are comparable to conventional products with long life expectancies.
Evaluation Criteria for Green Materials
Due to phenomenal growth in the construction industry, there is tremendous pressure on depleting earth resources such as soil, sand, stones, wood, etc. Production of building materials leads to irreversible environmental impacts. Using environmentally friendly building materials is the best way to build an eco-friendly building. The following criteria can be used to identify green materials.
Local availability of materials
The embodied energy of materials
% of recycled/waste materials used
Rapidly renewable materials
Contribution to Energy Efficiency of buildings
Recyclability of materials
Durability
Environmental Impact
Using the abovementioned criteria and assigning a particular rating (R1-R8) to each standard, an overall evaluation of the material can be made by summating the score obtained by any material in these ratings. Guidelines for assigning a rating to each criterion are discussed in the following text.
i) Local availability of materials
As far as possible, locally available materials are preferred to minimize the energy spent in transporting the building materials. Energy consumed in vehicles is the total energy spent on transporting materials starting from the place of manufacturing. Depending upon the distance from the material's manufacturing place, points for rating R1 can be allotted to the materials based on the following guidelines.
ii) The embodied energy of materials
Embodied energy assesses the energy required to manufacture any building material. This includes the energy needed to extract raw materials from nature, the energy used to transport raw materials to the manufacturing unit and the energy used in manufacturing activities to provide a finished product. Every building is a complex combination of many processed materials, each of which contributes to the building's total embodied energy. Embodied energy is a reasonable indicator of the overall environmental impact of building materials, assemblies or systems. The embodied energy of some building materials is mentioned in Table-2. Depending upon embodied energy of the materials, points for rating R2 can be allotted based on guidelines given in Table-3.
(iii) Percentage of recycled/waste materials used
Building materials can be manufactured using recycled materials or using waste materials. Using recycled materials helps the environment and the economy in several ways. A significant effect is lessening the need for manufacture with virgin, non-renewable resources, saving precious resources, energy and cost. Waste materials that would have ended up in landfills after their useful life can be reprocessed for use in other products. The use of various types of waste materials, such as fly ash, blast furnace slag, red mud, waste glass, marble dust, cinder, rice husk, coconut husk, banana leaves, jute fibres, rubber from automobile tires, etc., is demonstrated by research. Table-4 specifies guidelines for rating R3 for this criterion.
(iv) Use of renewable resources
Materials manufactured with renewable resources (i.e. wood or solar power) rather than non-renewable (i.e. fossil fuels) shall be preferred. Depletion of the Earth's resources is occurring at an alarming rate. The entire ecosystem is affected due to the continuous extraction of raw materials worldwide. As fossil fuel stock is limited, it may get exhausted very soon. By utilizing renewable energies, such as wind, solar, tidal, and renewable materials, such as wood (certain certified species which are rapidly renewable), grasses or sand, the impact on biodiversity and ecosystems can be lessened.
(v) Contribution to Energy Efficiency of buildings
Building construction and operation utilize a significant portion of the total energy produced. With little careful effort, designers and builders can reduce energy loads on structures, reducing energy requirements and the strain on natural resources. With proper orientation of the building concerning solar radiation to receive maximum daylighting, operable windows for natural cross-ventilation, use of passive cooling techniques (eliminating or lessening the need for air conditioning), walling unit with lower U values, roof insulation, water-saving devices and more efficient appliances can all work to reduce energy needs. Consideration of alternate energy source use, such as wind, solar and tidal power, can help alleviate reliance on traditional fossil fuel sources. The Bureau of Energy Efficiency (BEE) was set up by Govt. of India, which has formulated the Energy Conservation Building Code (ECBC),
which defines specific minimum energy performance standards for buildings. ECBC specifies minimum values for U-factor (U-factor is thermal transmittance which is the rate of transfer of heat through the unit area of a structure for the unit difference in temperature across the network., unit is W/m2-0C), Solar Heat Gain Coefficient (SHGC - the ratio of the solar heat gain entering the space through the fenestration area to the incident solar radiation. Solar heat gain includes directly transmitted solar heat and absorbed solar radiation, which is then reradiated, conducted, or convected into space) and Visual Transmittance (VT – it indicates the percentage of the visible portion of the solar spectrum that is transmitted through a given glass) with guidelines to be Table 6 specifies procedures for rating R5 for this criterion.
(vi) Recyclability of materials
The recyclability of the materials can be judged from the number of materials recovered for reuse after the useful life of materials/products or after the demolition of the building. Table - 7 specifies guidelines for rating R6 for this criterion.
(vii) Durability
Material replacement puts a strain on the Earth, its resources and its inhabitants. In making materials more durable and easy to maintain, manufacturers can help eliminate a costly, damaging and time-consuming process replacement process. Materials which are long-lasting and need little maintenance are preferred. Rating R7 for this criterion can be considered as mentioned in Table-8.
(viii) Environmental Impact
All materials used for the construction of buildings must not
harm the environment, pollute air or water, or cause damage to the Earth, its inhabitants and its ecosystems during the manufacturing process and also during use or disposal after the end of life. The material should be non-toxic and contribute to good indoor air quality. Worldwide industrial production uses billions of tons of raw materials every year. Pollution caubydthe by the excavation, manufacturing, use or disposal of a product can have far-reaching consequences on the Earth's ecosystem. Poor indoor air quality caused by VOC emission costs billions in medical bills and lost productivity to companies every year. The manufacturing, use, and disposal of PVC pose substantial and unique environmental and human health hazards because of its uniquely wide and potent range of chemical emissions throughout its life cycle. It is virtually the only material that requires phthalate plasticizers, which frequently include heavy metals, and emits large numbers of VOCs. In addition, during manufacture, it produces many highly toxic chemicals, including dioxins (the most potent carcinogens measured by man), vinyl chloride, ethylene dichloride, etc. When burned at the end of life, whether in an incinerator, structural fire or landfill fire, it releases hydrochloric acid and more dioxins. Products made with PVC may be avoided as far as possible. The following points should be considered for evaluating the environmental impact of the building materials, allocating ratof ing R8.
Classification of materials based on a scale
After evaluating the material for the criteria mentioned above and allocating points for rating R1-R8, totalling a maximum of 100 points, materials can be classified based on total points scored per the following guidelines.
Using the criteria, some materials are classified assuming specific data, as mentioned in Table-11.
B) Indoor Air Quality (IAQ):
Low or non-toxic: Materials that emit few or no CFCs, reproductive toxicants, or irritants, as demonstrated by the manufacturer through appropriate testing.
Minimal chemical emissions: Products with minimal emission of Volatile Organic Compounds (VOCs). Products that also maximize resources and maximize efficiency while reducing chemical emissions.
Moisture resistant: Product and systems that resist moisture or inhibit the growth of biological contaminants in the building.
Healthfully maintained: Materials, components, and systems that require only straightforward, non-toxic, or low-VOC methods of cleaning.
Systems or equipment: Products that promote IAQ by identifying indoor air pollutants or enhancing air quality.
C) Energy Efficiency:
Material, components, and systems that help reduce energy consumption in buildings and facilities.
D) Water Conservation:
Products and systems that help reduce water consumption in buildings and conserve water in landscaped areas.
E) Affordability:
Building product life-cycle costs are comparable to conventional materials and are within a project-defined percentage of the overall budget.
Construction activities can generate large amounts of waste
materials that then need to be disposed of. In addition, at the end of a
building's life, it may be deconstructed or demolished, generating significant
amounts of waste. Construction waste includes the waste that is generated during
construction activities (such as packaging, or the products of demolition) and
materials that are surplus to requirements (as a result of over-ordering or
inaccurate estimating).
Typical construction waste products can include:
Insulation and asbestos materials.
Concrete, bricks, tiles and ceramics.
Wood, glass and plastic.
Bituminous mixtures, coal tar and tar.
Metallic waste (including cables and pipes).
Soil, contaminated soil, stones and dredging spoil.
Gypsum.
Cement.
Paints and varnishes.
Adhesives and sealants.
Increasingly, there are options available in terms of
reusing and recycling materials, and reducing the amount of waste produced in
the first place, but despite this, a large amount of construction waste is still
disposed of in a landfill. 32% of landfill waste comes from the construction and
demolition of buildings and 13% of products delivered to construction sites are
sent directly to the landfill without having being used (ref. Technology Strategy
Board)
This can be an expensive process, as the 1996 Finance Act
introduced a tax on waste disposal on all landfill sites registered in the UK.
To help tackle this, a site waste management plan (SWMP) can
be prepared before construction begins, describing how materials will be
managed efficiently and disposed of legally during the construction of the
works, and explaining how the re-use and recycling of materials will be
maximised. For more information, see Site waste management plan.
It may be possible to eliminate a certain amount of
construction waste through careful planning. For example, steel formwork
systems might be capable of being used for concrete works which can then be
reused elsewhere on the project/s in place of timber formwork which is classed
as waste once it has been used.
Other types of construction waste may be capable of being
minimised; for example, products which are provided with reduced packaging or
those which are composed of recycled materials. There can also be opportunities
to re-use materials and products which are in a suitable condition (e.g. doors,
windows, roof tiles and so on), or exchange them for other materials with a
different construction site.
Materials and products which cannot be eliminated, minimised
or reused may have to be disposed of as waste. Before sending waste for
disposal, it should be sorted and classified to allow waste contractors to
manage it effectively and ensure that hazardous waste is properly handled.
The Problem
Disposal of public fill at public filling areas and mixed construction waste at sorting facilities or landfills has been the major approach for construction waste management. For sustainable development, we can no longer rely solely on reclamation to accept most of the inert construction waste. As such, the government is examining ways to reduce and also to promote the reuse and recycling of construction waste. Nevertheless, there will still be a substantial amount of materials that require disposal, either at public fill reception facilities or at landfills.
Today, we are running out of both reclamation sites and landfill space. With the current trend, our landfills will be full in mid to late-2010s, and public fill capacity will be depleted in the near future. In 2013, the mixed construction waste accounts for about 25% of the total waste intake at the three existing landfills. If there are insufficient public fill capacity and waste reduction measures being implemented, more public fill would probably be diverted to landfills and the landfill life will be further shortened.
