Earth structure materials may be as simple as mud, or mud mixed with straw to make cob. Sturdy dwellings may be also built from sod or turf. Soil may be stabilized by the addition of lime or cement, and may be compacted into rammed earth. Construction is faster with pre-formed adobe or mudbricks, compressed earth blocks, earthbags or fired clay bricks. Special Thanks to Sarthak Tapasvi for sharing his experiences and work.

1. Vernacular Eco-Architecture
SARTHAK KAURA

2. Adobe brick
making
20% - 40% clay content is ideal for making adobe bricks. The top soil is not used for making bricks. The soil is composed of
molecules of sand, silt and clay. The brick mixture consists of soil, small gravel and stone, water and dry pine needles. It is as per
the Apollonian Theory that the brick is held together and moulded once its dry.
Bricks are made using wooden moulds. The mould is wetted, the mix is thrown inside, patted and the top is levelled. The mould is
then lifted and the adobe is left on the ground. It is allowed to dry in the sun and turned to allow all the surfaces to dry. It is then
ready to be used or stored. The mix has to be just the right consistency – if it is too wet, it will slouch after the mould is removed. If
too dry, the mould will not slide out.
a) Throwing of the brick mix into wetted mould.
b) Compacting and pressing mix into the mould
c) Brick making site – adobes laid as close to each other as possible, left to dry
d) Smoothening of the surface to remove excess mix and making of frog
e) Lifting up the mould gently by holding diagonal corners.
f) Adobes drying in the sun
Adobe bricks being mould casted
on the flat ground, on the left it is
being directly casted on ground
whereas on the right, it is being cast
on a piece of slate (20in x 11in)

3. Adobe bricks are layed on ground and
each face is turned everyday so that it
dries from all sides. It takes 2-3 days
for the adobe bricks to dry if there is
constant sunlight. The bricks are layed
with minimum spacing to cover
minimum area so that maximum
bricks can be accomodated.
The mud for the adobe bricks is
generally procured by digging and
flattening the terraces on which the
structure is built.A similar terrace being
cleared and simultaneously the mud
being used to make the
bricks and the terrace being used to
dry the bricks.

4. Earth plaster work and earthen
renders
Pushpaji our local staff at Dharmalaya Institute working with and
guiding a group of volunteers to pug and mix the sifted mud
properly with gobar. Pugging of the mixture and allowing the
seepage of water in the mud particles is oneof the most vital
procedures of plaster making processes.

5. Minna using the sifting arrangement which composes of a
fine/course wire mesh fitted in a wooden frame and two
bamboo poles are used to support it at a suitable
inclinatrion. A piece of slate is used to rub the soil on to
the sieve to sift it.
Visible difference between the sifted and non-
sifted mud is evident. All the small particles of
stones are separated from the mud. The particles
of stone are a hindrance while doing the finer
coats of plaster. The coarse mud is used in the
garden.

6. The external plasterwork being done. The external
base coat plaster layer is about 0.5 inches thick.
This layer is not fine as it needs to be course to
provide a rough surface for the second of the
plaster to hold on to it. Bamboo scaffoldings are
made while constructing the walls so as to provide
a surface while making the roof and also while
plastering.
Pushpaji who is a trained mason, is doing
the interior plaster work. In the picture we
can see all the tools and paraphernalia used
for doing the plaster work : trowel, float,
water mug, pan et al. The surface is made
wet for the mud plaster to easily hold onto
the wall.

7. Mud plaster:
Three layers of plaster are usually applied to the adobe walls. The first layer has a 3:1 proportion of soil and sand respectively, with the addition of linseed (alsi) husk, which is
grown locally. The linseed husk adds insulative properties, water repellent properties and helps the mix to bind well. The soil used is passed through a coarse grade sieve with
a mesh of size ???. This process is called sifting, sieving or screening. It enables the removal of large stones and allows only smaller pieces of gravel to pass through. The
mixture of soil with gravel, sand, husk and water is then pugged and allowed to rest for a minimum of two days. Any uneven or irregular surfaces in the masonry are corrected
during the application of the base coat of plaster. Hence it is the thickest layer.
After the first layer is applied, it cracks on drying, above which the second layer is applied. This layer has the same proportions of soil and sand with the addition of cow dung
(gobar) in the ratio of 7:3 (mud : dung). The soil used for the second coat is sifted through a finer mesh of size ???, eliminating all stones and gravel. After pugging and resting,
the plaster is applied. This coat is much thinner than the first.
The final layer is done with a coating of fresh cow dung, to which natural or synthetic glue is added. Water and cow dung are mixed together to form a thick liquid, and applied
onto the wall surface with a cloth. This is traditionally called ‘lepai’. Alternatively, paper pulp can also be used for the final layer which is equivalent to gobar and requires less
maintenance.
An intermediate layer after the second layer may also be applied. It consists of the addition of the water in which linseed husk has been soaked for at least 2 weeks. The oils
from the linseed husk add water repellent properties to the plaster.
Gobar slurry being mixed into the
sifted mud for second coat plaster.
And small particles of stones being
picked from the plater mix

8. A final coat dung plaster composed of
turmeric and lime pigments being plastered
onto the walls for achieving a tint of colour.
Circular patterns and arcs
and strokes being made on
the wall .

9. Circular strokes of cow dung plaster with
colour pigment being done on the wall..
Circular patterns of cow dung plaster being
done on the mud floor, using a small piece
of cloth. The cloth is small as it drips less
although it takes more time to although.

10. earthbag porch
The entrance porch for a cottage at the Dharmalaya campus was constructed using earthbag technology. Since it was to be of a low height and non structural, no foundation trench
was required. The courses of earthbags were started at ground level. It was a total of 5 courses, with a proposed slate flooring on top. The outer faces are covered in mud plaster and
turf.
Course and sandy yet
little moist mud being
filled in the ACC
cement bags till they
are 2/3rds full.
Courses of earthbags
being laid on the two
lines of barbed wires
which are spanned on te
coarse to hold the
above coarse of bags
and act like mortar.
Once the courses earth
bags are laid, they are
compressed using this
wooden tamper.

11. The courses of
earthbags are
staggered so as to
avoid continuous
vertical joints.
Completed plinth wall
with 5 curses of earth
bags
Bricks or stones are used
to flatten out the barbed
wire so that the earthbags
can be laid on it.

12. Glass and soft/hard
plastic waste being
dumped in the
Since the plastic is
compressible, it is
topped with rubble.
Mud is added on to the
top of the rubble to level
the plinth.

13. Sifted mudis pugged an
mixed and allowed to sit
for a couple of days to
make this cob mix.
Balls of cob are made and
plopped onto the earth
bag wall to form a thick
layer of 1 inch.
Turf or patches of grass
with roots and mud on it is
dunked in water and
slapped onto the cobbed
wall, so that it holds onto
it and covers the entire
wall.
Once the entire wall is
covered in turf, it is
watered until it holds
roots into the cob.

14. slab roof for storeroom
Bamboo purlins laid on
the timber beam . A mat of
chachra is being spread
on the bamboos, which
acts as scaffolding.
Timber beams, bamboo
rafters and chachra from
beneath the slab
Chachra being spread
and the chicken wire
mesh being nailed to the
chachra for the
ferrocement slab.

15. Carpenters laying the
chahchra onto the the
bamboo purlins.
Rrocement One brick tall
wall constructed for curing
the freshly casted
ferrocement slab.

16. Slate flooring is a technique introduced by Didi Contractor in her neo-vernacular style approach.
Materials used: Slate tiles (find out dim and thicknes)
4” wide glass strips, cement, sand, pigment additive for cement
Procedure for laying slate floor:
Flooring is done only once masonry and installation of the roof has been completed. The area to be floored is levelled, and soling is carried out. Soling consists of stacking stones on
their vertical edges. Gravel is spread to fill interstitial gaps and a dpc is laid next. Above the dpc, a PCC bed (with cement:sand ratio 1:6) is laid, taking care to maintain the necessary
slope of the floor. Glass strips are placed while the cement is still wet, as per the required design. Finally, the slate tiles are placed and pressed gently into place. Rich cement is spread
in the space between tile and glass. At Dharmalaya, a green pigment is added to it for aesthetic reasons.
Finishing of the floor:
Slate tiles are first scrubbed clean using a locally available stone and a coat of clear varnish is applied. Since the surface of the slate is uneven, the varnish fills the gaps and makes the
floor easier to maintain.
Advantages of using glass strips:
-Cement expands and contracts with thermal changes, which can cause cracks in the floor and make it more susceptible to moisture and damage. The glass strips
help fragment the cement surfaces and thus reduce cracks.
-When a cement floor of large area is being laid, unsightly joints appear on the surface as laying of the cement is done in batches. To avoid this, glass strips are incorporated as
part of the design, improving aesthetics as well as making the cement laying procedure easier for masons.
- The strips act as a reference to check if the slope of the floor is being correctly maintained.
- In case of damage, it is easier to replace a tile without disturbing the surrounding ones because of the glass strips
slate flooring ( chakka flooring)

17. Material required: Centre-line drawing of the
proposed structure
Measuring tape, string (sut), right angle
(guniya), pegs/stakes, pick-axe, shovels,
compass, spirit level, lime powder etc.
The wall thickness executed for adobe
masonry in Dharmalaya Campus is generally
18” and the wall thickness for the wet blocks
(baked brick masonry) is 9”. The plan went
through went through a series of
modifications as per the shape of the contour
and the existing trees so as to cause
minimumdamage.
The datum was established in the beginning
and the extremities of the proposed structure
were roughly located to check the feasibility
of spanning the building across the contour.
The plan was adjusted as per the site
parameters.
The detailed centre-line procedure was
begun. The Pythagoras’ Theorem was used
at every junction to confirm the accuracy of
the right-angle. The Guniya and the Thread
(Sut) were used for connecting straight
centre-lines of the walls. The Lime Powder
was used to mark the mark the straight lines.
The offsets were marked on the either sides
of the centre-lines as per the wall thickness
and load carried by the walls. The walls
bearing the load of the first storey, were 3 feet
wide and whereas, the rest trenches were 2
feet wide.
line out for
duplex cottage

19. ex cavation of trenches

20. Above the plinth band up to the sill level, stone masonry walls are constructed. Above the sill level
the walls are built in Adobe. Adobe walls are built out of earth excavated from the site during
levelling. Mud is mixed with straw, sand and clay to balance the composition of earth and is
placed in the sun to dry. Usually bricks of size, 12 inches x 6 inches x 3 inches are used for 18
inch walls ; however different sizes are made for different applications as well. For example,
Queen brick is used for window ledges to bring in more light.
Wooden horizontal bands are a common feature in the buildings that survived the major 1905
earthquake and are majorly seen in the in the Kath Kuni style of architecture which is seen in the
northern part of Himachal Pradesh. In spite of Kangra region being densely forested, the wood is
excessively felled by the Government for export purpose. Therefore Didi Contractor has
substituted wood for reinforced concrete bands in the adobe brick walls. These horizontal bands
are tied together with vertical reinforcements built up within the main load-bearing corners. This
forms the protective skeleton embedded and keyed within brick work of the adobe buildings.
20% - 40% clay content is ideal for making adobe bricks. The top soil is not used for making
bricks. The soil is composed of molecules of sand, silt and clay. It is as per the Apollonian
Theory that the brick is held together and moulded once its dry.
Large particles of stone need to be picked out while making the brick mix. Dharmalaya Institute
is situated amidst a pine forest; hence dry pine needles are abundantly available. The needles
are added to the mix, while pugging it. The needles reinforce and give the brick additional
tensile strength. The pugging is important as it allows the water molecules to penetrate deeply,
in between the mud particles. The mixture should be allowed to rest as, it takes time for water
to percolate at a molecular level.
Tools used:
Plumb bob, water level pipe, trowel, hoe, bucket and tumbler.
Steps for constructing an adobe wall
The surface on which a new course of adobe has to be laid is first wetted. A layer of
mud mortar (~ 1” thick) is spread on it, in gradual patches. Corner bricks for the
external face of the wall are laid first. When the adobes are placed on the spread mortar, their
rougher face generally faces up and this is maintained as a constant throughout the masonry.
They are gently jostled into place, causing the mortar to spread completely on the entire face.
Their plumb is checked using a plumb bob and a string is stretched between them.
Subsequently, adobe blocks are laid in the desired bond pattern, taking care that the blocks do
not touch the string, but are as close as possible to it. This is done to maintain an accurately
vertical surface. A water level pipe is used to check the accuracy of the horizontal level of the
course. Once a course is complete, the gaps between adjacent adobes are filled in with mud
mortar. The process is then repeated.
Adobe brick walls

21. The hilly regions of Himachal, experience a lot of rain and also some snow, so it is very
important to have a roof that would address the climate and weather conditions.
So, an inclined roof is prevalent in most of the regions of Himachal.
The roofs used at Dharmalaya are either single lean-to or double lean-to roofs, depending
on the span of the structure. Didi Contractor keeps the inclination of her roofs from 30 - 45
degrees, with steeper slopes towards the north and the introduction of dormer windows and
skylights.
Pitched roof for cottage
The components of Roof :
Timber beams :
The most economical length of the timber beams is about 10 feet. Pine wood is generally
used for this purpose as, it is abundantly available in the near-by forests.
The tie beams in the trusses for large span roofs or the edge sleepers (dhansa) which rest
on the walls to distribute the load. Generally a piece of slate or broken glasses are put at the
junction where the timber member and the wall meet, to distribute load evenly. The common
beam size is 10 inches x 4 inches for ceiling slabs, but for the trusses, it is -
Rafters
:The rafters are of bamboo or sometimes, hollow steel pipe sections for the ceiling
roofs. The rafters are placed on the sleeper which rests on the wall and the ridge
beam at the top. The bamboo rafters are nailed to the respective junctions at the ridge
and the sleeper using 4 inch nails.

22. Ferrocement:
The ferrocement slab comes on the Chachra, it function basically to improve the strength of the roof
and also make it entirely leak-proof. The ferrocement slab is about 2-3 inches thick and has achicken
steel wire mesh, in it- which is tied and nailed to the chachra. the proportion for cement : sand is 1:6.
Sometimes mud is mixed with the cement to minimize the use of cement.
Purlins:
the purlins are basically pine wood batons which are nailed into the ferrocement slab at an interval of
12-13inches. the battons hold the slate tiles, which are inturn nailed into thepurlins.
Procedure:
The seasoned and treated bamboo rafters are first mounted onto the walls and the gable wall
construction is done around the wall edges. The Chachra is mounted and nailed onto the rafters.
Chicken mesh is tied to the Chachra. The cement concrete slab is cast onto the Chachra
scaffolding. Wooden purlins are nailed onto the ferrocement slab. The slate tiles are nailed onto the
wooden purlins the last.
Bambootreatment:
The purpose of the bamboo treatment is to reduce the pest and termite and other bore insect
damage. The insects attck the bamboo for the starch in it. Hence, traditionally the bamboo is
harvested on the new moon day when the photosynthesis cycle is such that there is minimum
starch in the bamboo trees. There are two traditional treatments for removing the traces ofstarch
from the bamboopoles:
#1 Leaving the bamboo poles in a "kihl" which is a stream of flowing water for about 28 days.
#2 Smoking the bamboo twice daily for 2-3 weeks in a bamboo kiln. Dharmalaya Institute has its
own bamboo kiln where the bamboos are treated.
Fibre glass sheets and Onduleum (recycled fibre glass sheets) are used for roofing where there is
a requirement for light.
Fixed glass or Fibre glass sky lights are also provided in the roofs.
The overhangs for the openings are designed with fibre glass roofing to get the light insidethe
building and protect the building from therains.
Roof is the major component that is responsible for temperature exchange in a building.
Insulating layers of rice husk and mud along with ferrocement does help in providing additional
insulation.

23. Wattle and daub
Coats of slaked lime
being applied onto the
bamboo weave mats
(kelta).
A timber frame with
diagonal braces and a
post, with a bamboo
weave mat nailed from
the outside, later the both
faces to be cob
plastered.