Decision making for selection of material for constructing “Green Building” ; Green technology

Decision making for selection of material for

constructing

“Green Building”

Green technology

GREEN TECHNOLOGY

Technology that has the potential to significantly improve environmental performance relative to other technology

SECTORS OF GREEN TECHNOLOGY

Agriculture.

Energy.

Buildings.

Transportation.

Water and waste management.

WHAT ARE GREEN BUILDINGS

“Green” Buildings are high performance structures that also meet certain standards for reducing natural resource consumption

Green” or “Sustainable” buildings are characterized by:

efficient management of energy and water resources

management of material resources and waste

restoration and protection of environmental quality

enhancement and protection of health and indoor environmental quality

reinforcement of natural systems

BENEFITS OF GREEN BUILDINGS

Environmental benefits.

Social benefits.

Economic benefits.

GREEN BUILDING MATERIAL

Green building materials are composed of renewable, rather than nonrenewable resources. Green materials are environmentally responsible because impacts are considered over the life of the product

DECISION MAKING

STEPS

Problem Recognition

Information Gathering

Principles for Judging Alternatives

Brainstorm and Analyze different choices

Evaluation of Alternatives

Select the best option

Execute the decision

Evaluate the results

PROBLEM RECOGNITION

PROBLEM RECOGNITION

Problem recognition is the most important step in order to make the best decision of construction material for green buildings.

PROBLEM RECOGNITION

The major problem is the choice of the construction material that creates less pollution, less disruption of ecosystem, less consumption of energy.

It must be:

Reliable

Durable

Easily available

Environmental friendly

The decision of the selection of such material often involves:

Multiple criteria.

Multiple stakeholders.

Quantifying multiple criteria in monetary terms.

Attractive alternative with significant quantitative analysis

INFORMATION GATHERING

INFORMATION GATHERING

Selection of suitable green building material options can be influenced and determined by numerous preconditions, factors and considerations.

For such purpose adequate information related to the essential factors or variables effecting the decisions in the choice of materials is collected and gathered.

In this stage, wide range of research and information is reviewed to:

Examine impacts of current procedures used for selecting locally-sourced or recycled building materials on overall performance of buildings.

Identify gaps and problems with previous research in the area of material-selection tools or systems developed for green buildings.

Learn from strengths and weaknesses of the expert systems, especially developed to manage the material-selection process.

GRAPH SHOWING EXTENT OF

PARTICIPANTS’ AWARENESS OF EXISTING

SYSTEMS FOR GREEN BUILDING MATERIAL

INFORMATION GATHERING

For assessing building material sustainability the information regarding the following framework of factors is collected:

Information regarding the general site factors is collected.

The concerned Environmental and health factors are determined.

The sensorial factors are taken into consideration.

The related socio cultural factors are analyzed.

The cost and economic value of the material is evaluated.

The technical factors are also considered in the selection of material.

VARIANCE OF INTEREST IN THE

USE LOCAL AND RECYCLED

BUILDING MATERIAL OPTIONS

PRINCIPLES FOR JUDGING

THE ALTERNATIVES

PRINCIPLES FOR JUDGING

THE ALTERNATIVES

In this step the base line criteria for judging the alternatives is set up. Some of the key principles for judging the alternatives are as follows:

a) Cost effective

b) Environmental friendly

c) Ensure energy conservation

d) Maintain Indoor Environmental Quality

e) Ensure water Quality and Conservation

f) High capacity and durable

BRAINSTORMING

BRAINSTORMING Clay bricks

Steel

Hemp block

Timber

Compressed earth block

Extruded earth block

Plastic

Clay plasterboard block

EVALUATION OF ALTERNATIVES

EVALUATION OF

ALTERNATIVES

Clay bricks

This is an unfired clay brick, commonly used in cobwork.

They can be used for non-loadbearing walls or infills in lumber-frame constructions.

PROS

Clay bricks

Fireproof

Resistant to seismic activity

Inexpensive.

CONS

Extreme weather may cause degradation of the surface due to frost damage

Services of a qualified structural engineer may be required.

Brick adds a lot of weight to the foundation.

Lower tensile strength

STEEL

Steel

A steel building is a metal structure fabricated with steel for the internal support and for exterior cladding.

Steel buildings are used for a variety of purposes including storage, work spaces and living accommodation.

PROS

Steel is a "green" product as it is 100% recyclable

Design flexibility

Easy to Install

CONS

Heat conductivity

Steel conducts heat 310 times more efficiently than wood.

Subjected to corrosion

Faulty design leads to the corrosion of iron and steel in buildings.

HEMP BLOCK

Hemp block Hempcrete is a bio-composite base material consists of fibers from the hemp plant mixed with sand and lime.

PROS

Lightweight cementitious material

Best insulating material

weighing about a 7th or 8th of the weight of concrete.

Repellent to white ants and fire ants

Discouraging the growth of mold

Renewable Resource

Rapid growth of fiber without fertilizer

CONS

It’s carbon negative because it sequesters carbon when used as a building material.

it’s not loadbearing

A frame is required to carry the loads

Transportation Cost

Environmental cost

Environmental footprints

TIMBER

Wood is a product of trees, and sometimes other fibrous plants.

It is used for construction purposes when cut or pressed into lumber and timber, such as boards, planks and similar materials.

Wood has been used as a building material for thousands of years in its natural state.

PROS Used to make floors, walls,

supports and roof frames

High Strength

Easy to work with

Versatile

Potentially renewable

Biodegradable

CONS

Some timber is non-renewable

Treated with toxic chemicals

Causes deforestation

It is not Eco-friendly

COMPRESSED EARTH

BLOCK

Compressed earth block

A compressed block out of an appropriate mix of:

a. Dry inorganic soil

b. Non-expansive clay

c. Aggregate

d. Cement

Traditional blocks of this nature, such as adobe blocks, were sun-dried, but modern versions are mechanically compressed.

PROS Provide a source of employment

Non-toxic protection

Don’t off gas VOCs

Sound resistant

Fire resistant

Insect resistant

Mold resistant

Highly affordable.

Proven durability.

Little waste generated.

Material re-use.

CONS

Slower to build with, when compared to wood construction.

EXTRUDED EARTH BLOCK

Extruded earth block Theses are the unfired molded blocks, "extruded," into a continuous length in a machine, and then cut into smaller blocks.

PROS

They can be use as an internal partition walls

They prove to be good acoustic wall structure

CONS

Unfired blocks degrade to mud when immersed in water

The soil required for Extruded earth is much sandier than the one for fired earth

Thus the soil is more abrasive and the machines get damaged at a much faster rate

They are not cost effective

PLASTIC

It is a product of synthetic materials derived from petrochemicals.

Polymers being used in construction industry such as:

1. Polyethylene

2. Polypropylene

3. Polyvinyl Chloride

PROS

Use to make window frames, water pipes, floor & wall coverings etc.

Light weight

Highly durable

Resistant to damp, water and pests

CONS

Made from non-renewable resources

Intensive energy required to produce it

Highly polluting material

Off gas VOC’S

can not be easily degraded and decomposed

CLAY PLASTERBOARD

BLOCK

Clay plasterboard block It has been made from :

a. Un-fired clay

b. Recycled Dry-wall

It use in the flat orientation for greater loadbearing strength.

PROS

Health benefits

High breathability

Low environmental impact

Cost Effective

Clay plasters regulate relative interior humidity between 40% to 70%.

By keeping RH between 40% to 70% research has shown that the likelihood for airborne infectious bacteria and virus to survive is the lowest.

Keeping RH between 40 to 60% also prevents building materials from off gassing toxins, such as formaldehyde.

Highly Sustainable products as:

a. 100% bio-degradable

b. 100% recyclable

c. 100% reusable

CONS

It may contains toxic chemicals

It may contains glass fibers

Expensive

Difficult to Repair

Plaster also changes color slightly as it ages.

SELECTION OF BEST

ALTERNATIVE

COMPRESSED EARTH BLOCK

We have decided to use the “compressed earth block material” for the green building as it has enormous benefits

Economically feasible

The earth used in the production of the CEBs is actually subsoil which leaves the nutrient rich topsoil on the surface.

This healthy topsoil can then, still be used for agriculture.

EXECUTE THE DECISION

EXECUTE THE DECISION

Once the Compressed earth block material is decided to use as a green building material, we have to execute it by following a sequence of activities like taking approval from Environmental Protection Agency & For execution, we involve the NGO SECTOR, public participation and the other relevant sub-ordinates.

EVALUATE THE RESULT

Compressed Earth Block has been selected because of the following reasons:

CEBs use a uniform building component size.

Rapid construction & No need of pre-heating before use.

High compressive strength can easily hold a roof

They provide durable and weather resistant construction

Unskilled labor can be hired for construction

Environmentally viable.

REFERENCES

Ogunkah. I., Yang. J. (2012) Investigating factors affecting material selection. Buildings. 1-32

Heerwagen. H. J. (2000). Green buildings. Building research and information. 28 (5). 353-367.

http://www.americanlimetechnology.com/what-is-hempcrete/

http://www.diynetwork.com/home-improvement/all-about-green-building-materials/index.html

http://www.readersdigest.com.au/types-of-building-materials