2. ❑ The selection of building materials should meet the needs of
local conditions to improve quality of life for the most
needed ones by building new structures and/or by
improving existing structures.
❑ Findings show that up to 60 % of the total cost of a low-
income housing project is allocated to engineering design
and construction materials.
❑ Moreover, walls constitute up to 50% of the total cost of
materials and up to 45% of total construction time.
❑ Material origin, production techniques and labour
requirements all have major impacts on the selection of
wall building material.
❑ The analysis of particular local conditions will determine
where materials are most suitable for their use.
❑ Furthermore, the time when materials and techniques were
/ are mostly used will determine whether they could be
classified as traditional or contemporary.
❑ The regularity of use will determine whether materials and
methods could be classified as conventional or alternative.
❑ Use of low cost building materials for construction of low
cost housing increases the access to buildings by low
income group peoples.
❑ Low cost housing can be achieved by use of efficient
planning and project management, low cost materials,
economical construction technologies and use of alternate
construction methods available.
❑ The profit gained from use of such methods can decrease
the cost of construction and make the low cost housing
accessible to all.
❑ The use of low cost alternate building materials also
prevents the rise of construction cost due to use of scarce
building materials which eventually increase the cost of the
project.
INTRODUCTION
3. Selection of Low Cost Building Materials for Low Cost Housing
❑ The first step to low cost building material selection is to
select eco-friendly building materials. This also enhances
the sustainable design principle.
❑ The life cycle of a building is pre-building, building and post-
building stages.
❑ Each stage of building should be such that they help
conserve the energy.
❑ These three stages indicate flow of building materials
through different stages of a building.
❑ Pre-building stage mainly consists of manufacture which is
subdivided in processing, packing and transport.
❑ The building phase mainly consists of construction,
operation, maintenance and disposal last the stage where
the material can be recycled or reused.
MATERIALS SELECTION CRIETRIA
4. ❑ Manufacturing of Low Cost Building Materials :-
□Environmental friendly
□ Improve technologies for production
□ Reduction in waste generation
❑ Use of Recycled Waste as Building Materials:-
□ Waste produced can be used for the production of a
material cheaper in cost
❑ Use of Natural Low Cost Building Materials :-
□ Natural materials are sustainable and environmental
friendly
□ Materials like stone , wood ,lime ,bamboo ,sand have low
embodied energy
❑ Use of Local Building Materials :-
□ Reduces transportation dependence
□ Suitable for local environment
❑ Use of non-toxic Building Materials :-
□ Materials to be free from any kind of toxins
□ Higher air cycling required if any highly organic volatile
compounds are used
❑ Longevity, Durability and Maintenance :-
□ Use of durable construction materials decreases the
maintenance cost
□ Low maintenance cost saves a lot of building operating
costs
❑ Recyclability and Reusability :-
□ In a form so that it can be recycled or reused. Ex- Plastics
❑ Biodegradability :-
□ Decompose naturally when discarded
□ Not produce toxic gases while decomposition
❑ Using Energy Efficient Building Materials
□ Energy efficiently of a building material can be measured
through various factors as its R value, shading coefficient,
luminous efficiency or fuel efficiency. Energy efficient
materials must reduce the amount of generated energy.
MATERIALS SELECTION CRIETRIA
5. ❑ Low cost Housing materials can be broadly classified
into natural materials and manmade materials according
to the source of the building materials.
LOW COST HOUSING MATERIALS
NATURAL MATERIALS :-
❑ Random Straw or Coconut Fibres Stabilised Soil
❑ Bamboo
❑ Compressed Earth Block
❑ Non –erodible Mud Plaster
❑ Straw
❑ Fibre Cement Composites
❑ Bagasse Composite boards
MAN MADE MATERIALS :-
❑ Fly Ash
❑ Coal Washery Rejects
❑ Aerocon Panels
❑ Ferro Cement 5
6. NATURAL MATERIALS :-
1. RANDOM STRAW OR COCONUT FIBRES STABILISED SOIL
• Ancient construction material used in many countries
• Have both strength and durability
• Compacted material
• 1% of straw increases the strength by three time as
compared to no straw
• Coconut fibres increases the durability
• Sulphur coating enhances the water resistance
2. COMPRESSED EARTH BLOCK
• Raw earth stabilized by cement or lime
• Also known as Adobe bricks ,light in weight
• Non toxic
• Fire resistant ,Sound resistant
• Low transportation cost
• Insect resistant as they are very dense
• Available in customizable sizes
• Used in stucco work for exteriors
7. NATURAL MATERIALS :-
3. BAMBOO
• India is the largest producer,50% of world production
• Easily affordable
• Easy assembly and long durability
• High tensile strength, than steel
• Fire resistant unto 4000 deg C
• High elasticity hence used in earthquake prone areas
• Low weight –easy for transportation and assembly
DETAILS:-
The types of bamboo foundation identified are:
• Bamboo in direct ground contact
• Bamboo on rock or preformed concrete footings
• Bamboo incorporated into concrete footings
• Composite bamboo/concrete columns
• Bamboo reinforced concrete
• Bamboo piles
Floors :-
▪ structural bamboo elements
▪ bamboo decking
Walls :-
This infill can take many forms:
▪ Whole or halved
▪ bamboo culms
▪ Whole or halved vertical or horizontal bamboo
▪ culms, with or without bamboo mats
▪ Split or flattened bamboo, with mats and/or plaster
▪ Bajareque
▪ Wattle (wattle and daub, lath and plaster, quincha)
▪ Woven bamboo, with or without plaster
▪ Bamboo panels
8. NATURAL MATERIALS :-
4. NON-ERODIBLE MUD PLASTER
• Economical process of preventing mud walls from erosion
• Mud mixed with bitumen and kerosene oil
• Resistant to water
5. STRAW
• Fire resistant
• Thermal insulation
• Soil and Moisture insulation
• Non toxic
Life Extended Thatch Roofing
• Treating with copper sulphate solution decreases the
biodegradability
• Treatment of roof surface with phosphorylated spray or
CNSL oil imparts
o Water proofing
o Termite resistance
o Fire resistance
o Weathering resistance
Improved Thatched Roofing
• CBRI advise to add mud platers in between to increase
fire and water resistance.
9. NATURAL MATERIALS :-
6. FIBRE CEMENT COMPOSITES
• Natural fibre used with cement as an alternative building
material
• Fibres used like bagasse , cereal straw, corn and cotton
stalk ,kenalf/rice husk
• Imparts
o Light weight
o High strength to weight ratio
o Corrosion resistance
o High fracture toughness
o High flexibility o Resistance to cracking
o Add workability
7. CEMENT COMPOSITES
BAGASSE CEMENT – BOARDSAND PANELS
• Fibrous matter after sugar is extracted
• Sugarcane bagasse and Portland cement is mixed
• High density boards .
BAGASSE P.V.C BOARDS
• Sugarcane bagasse and PVC is mixed as a binder
• Inherent self extinguishing property
• Used in door shutters, sanitary fixtures, pipes, cable,
cabinets.
BAGASSE P.V.C BOARDS ( JUTEAND COIR )
• Widely available in India .
Coir-CNSL Board
o used for window and door shutter, partitioning, false ceiling,
furniture etc.
o Single layer flat pressed medium density board
o Low water absorption, workable with wood tools
o Paintable, pre laminable, screw able
10. NATURAL MATERIALS :-
BAGASSE P.V.C BOARDS ( JUTEAND COIR )
Coir-CNSL Thermal Insulation Board
o Coconut fibres as reinforcing material
o CNSL as natural binder
o Low density for moderate thermal insulation.
Jute - Coir Composites
o Economic alternative for wood
o Eg-coir ply boards with jute face veneer, coir plus waste
rubber inside.
Coconut And Wooden Chips Roofing Chips
o Coconut fibres and wooden chips soaked in water for 2
hours and then drained off
o Mixed with cement and layedover corrugated mould kept
under pressure for 8-10 hours
o CNSL oil can also be used as a natural binder
Coir-CNSL Thermal Insulation
Board
11. NATURAL MATERIALS :-
TABLE :1 Availability of natural fibre in India and its application
in building materials
ITEM SOURCE APPLICATION IN BUILDING MATERIALS
RICE HUSK RICE MILLS As fuel , for manufacturing building
materials and products for production
of rice husk binder , fibrous building
panels , bricks, acid proof cement.
BANANA
LEAVE /
STALK
BANANA PLANTS In the manufacture of buildings boards
, fire resistance fibre board.
COCONUT
HUSK
COIR FIBRE
INDUSTRY
In the manufacture of building boards
, roofing sheets , insulation boards ,
building panels , as a line weight
aggregate , coir fibre reinforced
composite boards.
GROUNDNUT
SHELL
GROUNDNUT OIL
MILLS
In the manufacture of buildings panels
, building blocks ,for making chip
boards , roofing sheets , particle
boards.
JUTE FIBRE JUTE INDUSTRY For making chip boards, roofing sheets
, door shutter
RICE/ WHEAT
STRAW
AGRICULTURAL
FARM
Manufacturing of roofing units and
walls panels / boards.
SAW MILL
WASTE
SAW MILLS /
WOOD
Manufacture of cement bonded
wood chips , blocks , boards , particle
boards , insulation boards , briquettes .
SISAL FIBRES SISAL
PLANTATION
For plastering of walls and for making
roofing sheets , composite board with
rice husk , cement roofing sheet ,
roofing tiles , manufacturing of paper
and pulp.
COTTON
STALK
COTTON
PLANTATION
Fibre boards , panel , door shutters ,
roofing sheets , autoclaved cement
composite , paper , plastering of walls
12. TABLE :2 The properties of building materials in consideration.
PROPERTIES BAMBOO CONCRETE
BLOCKS
FERROCEMENT
AND AEROCON
PANELS
STRUCTURAL Works better with
moisture in shear
forces; have high
flexibility than
steel and lower
young’s
modulus.
Can be given
strength as per
required ; less
mortar joint as
size bigger
which
increases
stability.
Light weight and
requires no wet
plastering
(Aerocon); high
strength , low
density and high
crack resistance of
mortar . (ferro
cement ).
THERMAL Excellent Excellent Excellent
TEMPERATURE
AND WATER
RESISTANCE
Moderate Excellent Excellent
BUILDABILITY Moderate Excellent Excellent
COST (IN RS/
SM )
Depends on
thickness 1*
31.25 Depends on
thickness 2*
PROPERTIES FIBRE – CEMENT
COMPOSITES
FLY ASH BRICKS
STRUCTURAL The light weight , high
strength to weight
ratio , corrosion
resistance , crack
resistance , flexibility ,
lightness.
Reduce pollution , save
energy , reduce mercury
pollution and cost 20 %
less than traditional clay
brick manufacturing ,
high strength , lower
water penetration .
THERMAL Excellent Excellent
TEMPERATURE AND
WATER RESISTANCE
Moderate Excellent
BUILDABILITY Excellent Excellent
COST (IN RS/ SM ) Depends on fibre 3* 62.66
13. TABLE :2 The properties of building materials in consideration.
PROPERTIES MUD
BLOCKS
COMPRESS
ED
RICE HUSK STRAW BALE (WITH
BRICKS)
STRUCTURAL Economic
and
energy
efficient .
Pozzoloanic ,
economical ,
corrosion resistance
increases , light
weight final product .
Stable and high
load bearing
power.
THERMAL Excellent Moderate Moderate
TEMPERATURE
AND WATER
RESISTANCE
Excellent Depends on
composition as it is
used as admixtures.
Also depends on
brick composition
as it is mixed with
the brick and with
mud.
BUILDABILITY Excellent Moderate Moderate
COST (IN RS/
SM )
15.625 NA NA
NATURAL MATERIALS :-
MAN MADE MATERIALS :-
1. FLY ASH
• Mineral residue after burning burning coal and fine glass
• Constitutes of silica, alumina and iron .
Fly Ash Bricks
o Class C fly ash and water
o Due to high calcium oxide its self cementing
o Energy efficient
o Lower water penetration, light weight, thermal insulation
14. MAN MADE MATERIALS :-
2. COAL WASHERY REJECTS BRICKS
• Left over after fluidised bed combustion
• Uses water and reduces air and land pollution
• Energy efficient
• Red mud, coal ash, etcfrom large scale industries can be
used
• These are mixed with lime pozollona and cement to form
bricks
3. AEROCON PANELS
• Inorganic bonded sandwich panels
• 2 fibre cement sheets engulfing a Portland cement mix
with fibres of silica's and micaceous aggregates
• Light weight, thermal insulation, fire and sound resistant
• Termite and weather resistant
• Suitable for seismic or cyclone prone zones
2. COAL WASHERY
REJECT BRICKS
3. AEROCON PANELS
15. MAN MADE MATERIALS :-
4. FERRO CEMENT
• Thin walled versatile high strength cement based
composite material
• Cement mortar reinforced with 2-3 layers of wire mesh
• Light weight high strength
PLASTER
Calcium Silicate Plaster
o Derived from Wollanstonite naturally occurring
calcium silicate
o Does not emit VOC or any other harmful gases
o Gives a smooth finish.
Fibre Reinforced clay plaster
o Natural or artificial fibre(polypropylene)
o Achieve better sticking properties
o Less Brittles
ROOFING
Bamboo Matt Roofing Corrugated Sheets
o Better than clay and Mangalore tiles
o Preferred for semi permanent structures
16. CHARACTERISTICS OF LOW COST
BUILDING MATERIALS :-
1. Easy to manufacture
2. Easy affordability
3. Easy Erection/commissioning
4. Faster & cheaper construction
5. Effective Waste utilization
6. Energy efficient and Environment friendly
ESTIMATED COST SAVINGS ON
USING INNOVATIVE / COST
EFFECCTING BUILDING
MATERIALS / TECHNOLOGIES :-
SR. NO COST – EFFECTIVE
TECHNOLOGIES
IN PLACE OF
CONVENTIONAL
OPTIONS
% OF
SAVINGS
1 85 mm thick sloping RCC RCC 110 MM 30
2 Ferrocement shell roofing RCC 40
3 RCC plank over RCC joists RCC 10
4 RCC door frames Timber frames 30
17. ESTIMATED COST SAVINGS ON
USING INNOVATIVE / COST
EFFECCTING BUILDING
MATERIALS / TECHNOLOGIES :-
SR. NO COST – EFFECTIVE
TECHNOLOGIES
IN PLACE OF
CONVENTIONAL
OPTIONS
% OF
SAVINGS
5 Frameless doors (only inserts) Frames and shutters 50
6 Ferrocement door shutters Timber shutters (second
class timber )
30
7 RCC window frames Timber frames 30
8 RCC jallies Timber windows /
ventilations
50
9 Precast RCC shelves units Timber / concrete 20-35
10 Precast Ferrocement shelves Timber / concrete 35-45
11 Ferrocement manhole
covers
Steel / concrete 50-40
12 Ferrocement water tank Rigid PVC 60
13 Precast thin lintels RCC lintels 25
14 Precast sunshades Cast sunshades 30
15 Ferrocement sun shades –
cum – lintel
RCC lintel-cum-
sunshades
50
16 Brick arch for lintels RCC lintels 30