Green Technologies for Buildings

Dasarathi GV (normally called Das)

Disclaimer

I am not any of theseCivil engineer, Architect, Environmental engineer

Just a dumb mechanical engineer who used his knowledge of mechanical engineering and lack of money to build an environment-friendly house.

What I do for a livingFounder-Director Cadem Technologies Pvt. Ltd., BangaloreMake software products for Computer Aided Manufacture

What is environment-friendly construction ?

Popular definitionReducing energy and water consumption.- rain water harvesting, water recycling, solar energy.

Expanded definitionReducing construction material + reducing energy and

water consumption.

Problem 1 – Overdesigned structures

How many years will this structure last ?

How many years will it be allowed to last ?

Average house is built to last a couple of thousand years, but is typically broken down in 25 years because the next generation’s requirements have changed.

Problem 2 – Skewed priorities

Essentials - water, power, fresh air, greenery.Rain water harvesting, grey and black water harvesting, solar

panels for power, trees.

Non-essentials : Floor tiles, expensive walls, unnecessary concrete decor, jacuzzi.

We spend on non-essentials. If there is any money left over, we spend on essentials. Should be reverse.

The fix

Extend the tenets of environment-friendly living to construction.

Reduce, Reuse, Recycle

Reduce : Reduce the consumption of materialReuse : Reuse an already used material, as it is.Recycle : Change the form of an already used material

by heat, chemical reaction, mechanical force.

Our current thinking

What is this ?

What is this ?

Construction waste.

Nice flooring

What we should think

What is this ?

What is this ?

Reusable construction material.

Waste of material,money, time.

Ideas for Reuse, Reduce in Construction

Used in a home that's 2 years old and still standing.

Reduce 1 – No concrete roof

Bamboo corrugated sheet instead of concrete roof.

Concrete roofs trap heat during day, radiate it at night, hence get hot.

Bamboo roof does not trap heat.

Reduce 2 – No airconditioners

Fans instead of air-conditioners.

Because no concrete roofs, no walls, lots of windows.

Reduce 3 – No exhaust fan in kitchen

Natural draught instead of exhaust fan.

Opening above the kitchen platform for exhaust.

Reduce 3 – No flat, smooth walls

0.25” plaster instead of 1.5” plaster on walls.

Walls are ordinary (not wire-cut) brick. Our walls are not flat, undulate with the shape of the bricks.

Cement and sand for plastering reduced by 75%.

Reduce 3 – No tiled floors

Plain grey cement floors instead of tiled floors.

Saving : Rs. 2 Lakhs.

Reduce 4 – No walls

Walls are meant to keep the weather out.Windows are meant to let the weather in.

Bangalore has pleasant weather through the year, there's no need to keep it out. Hence no walls.

Bonus : Birds and animals for company.

Reuse 1 – Wood from packing cases

Wood : Pine wood from packing cases.

Reuse 2 – Glass from demolished buildings

Glass for walls, windows : 75 % from demolished buildings.

Reuse 3 – Reused toilet fittings

Commodes, washbasins, taps showers from demolished buildings.

Fittings for 2 toilets cost Rs. 7000. New would have cost Rs. 50,000.

Reuse 4 – Reused kitchen sinks

Kitchen sinks from demolished buildings.3 sinks cost Rs. 5000. New would have cost Rs. 25,000.

Reuse 5 – Lamp shades from dust bins / footpath

Savings : 75 % cheaper.

Reuse 6 – Discarded paving stones from footpaths

Granite paving stones in garden are discards from city's footpaths – they were replaced by tiled footpaths.Savings : 90 %.

Reuse 7 – Rain water harvesting, grey water harvesting

Rain water harvesting tank capacity 20,000 l. - 4 times the legal requirement.Grey water harvesting – water for garden.Black water harvesting proposed.

The net result

Construction cost : 40 % of normal. Rs. 17 Lakhs.Construction time : 50 % of normal. 7 months.

Aesthetics : 'Kachra house' or 'Kuppe veedu' was the 'House of the month' in a home interiors magazine.

Just remember these

1. Build to last 25 years, not 2500 years.

2. Prioritize essentials - water, power, fresh air, greenery. Spend on essentials. If there is any money left over, do not spend on non-essentials. Scale up the essentials – more solar power, more rain water harvesting.

3. Build to impress yourself, not your neighbours.

4. The principles used in my home are universal. Can be used in any building – home, office, school, hospital.

for listening patiently to me, and not falling asleep.

More about the house here : www.lowcarbonlife.in