Recipe for Earthen Plaster using lime, husk & cow urine for a beautiful wall finish of Devapriyan Kanjankat‘s Cob home from the Coast of Kerala.
Article by Natural builder Becky Little about how she used clay plaster in her home & studio space to render an interior wall.
Flowing Palm Leaf Lean-To roof
Rain started in Tiruvannamalai, so we started our roof work to protect our Cob walls. Below is the video of doing our Palm roof
We took our center point for the main wooden pole away from the structure to get more height for shade as well as for having a loft near top most area of the center wooden pole.
We are lucky enough to get this 18 feet height wood from nearby village. Tied rope at the top most point in different direction to see the pitch of the roof as you see in the above photo. Roof pitch was not enough so we attached bamboos to add height for the main pole.
Main 22 feet bamboo poles act as the main rafter to hold the weight of other bamboos and palm leaf cover on top
Top view from the main wooden pole showing the shape of the foundation and the bamboo columns to hold the main rafters. So the lover part of the roof started taking its shape naturally.
Marking on Earth using natural colours for cob foundation
We really want to Re use old casuarina poles and bamboos (poor man’s timber). Casuarinas will get harder when it gets old. Most of the materials were ready on site. We collected different stones in different size and shape from nearby land for a Rock game.
We started with common living room as first phase for our cob homes. Two natural colours were used for the grid as well as for the curved wall of cob foundation. For the basic grid points we used red mud and for curves we used lime powder.
This grid pattern really helped for marking curved walls. Cob walls can be attached for future expansion, so we kept two tales on both ends. After digging the foundation we kept PVC pipe for the casuarina poles and pour cement inside, so that the poles wouldn’t get damaged.
For foundation mortar we thought of using cob and lime. Here we mixed lime and red mud in 1:10 ratio and kept it side by side. We are planning to keep it for minimum 4 days and drill small holes and pour water on top of the piles.
Mean time climate in Tiruvannamalai, Tamil Nadu is changing. There are chances for rains and we had heavy rains in other part of India this year. So we called our bamboo worker friend for help and going to start roof work to prevent our Cob walls.
Cob is one of many methods for building with raw earth, the world’s commonest construction material. Cob meaning “a lump or rounded mass”. It’s a traditional building technique using hand formed lumps of earth mixed with sand and straw. Building with cob is a sensory and aesthetic experience like sculpting with clay. In history of buildings the most ancient buildings are either made of stone or cob. While in India we can still find many houses made of Cob, Stone, Lime and other natural materials. Cob is very resistant to weathering. Because of its porous nature, it withstands long periods of rain without weakening. However, too much exposure is best avoided by the “boots and cap” strategy: wide roof eaves to protect the walls and an impervious foundation. In windy areas a lime-sand plaster is traditionally used to protect exterior cob walls. Cob houses are widely constructed in the ancient India and are still alive in Indian rural areas.
Thannal hand sculpted homes started working Cob Houses in the foot hills of Arunachala Mountain in India for Thannal Workers in 4356 SQFT land. We are planning 3 cob cottages, Common Living area and a common kitchen. One cottage will have upper loft, so our other natural building friends like POOSHers can come, stay and help us to share more information about natural building techniques.
We started planting trees one year before, specially in West side to prevent the structures from summer sun. So we planted lots of Agathi Keerai (Sesbania Grandiflora) is also known as Hummingbird Tree Leaves or August Tree Leaves. You can read about these plants in Arunachala grace and indus ladies
Our site is located near Eri Karrai near Ramana Ashram, Tiruvannamalai. Eri means a lake or a large tank for water in Tamil. Land soil is loose and has clay content. So rain water may get locked in our land. First what we have done is to dig a trench around the site, so that the water will not get stuck.
Drainage around the site
We thought of doing this cob homes after summer and our first work before drainage on this land, as we mentioned in our earlier post in Never mind blog was doing a sculpture called Giri Vanakam (Bow to a mountain).
Giri Vannakam sculpture in Tiruvannamalai
The drainage really helped our plants to grow faster; the great help made by this drain is to protect our Temple Tree or Plumeria. This Tree has been plucked two times on its budding stage .First time an OLLA (Coconut leaf) Worker by mistake and next time by a grass cutting village women. Both the times our soul coordinator, Jithu (Vijith.P.N) helped this Chiranjeevi (means one who lives forever) Tree and planted this wounded tree safely. It seems like this plant want to grow in our area. Thanks to Jithu to save this beautiful tree. Now this summer our tree started flowering.
Jithu in wattle and daub construction and our Temple tree
While designing Thannal cob homes for Thannal workers we kept this Growing tree as our center point in our design composition, so the whole structure started growing around this tree and our drain.
Thannal cob house plan for thannal workers